Next Article in Journal
Enhancement in Corrosion and Wear Resistance of FeCoNiCrAl High-Entropy Alloy Coating Through Dual Heat Treatment with 3:1 N2/H2 Atmosphere
Previous Article in Journal
Effect of Nanoclay on the Performance Characteristics of SBS-Modified Asphalt Concrete Mixtures
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Coatings
Volume 15
Issue 9
10.3390/coatings15090985
coatings-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Hydrophobic, Durable, and Reprocessable PEDOT:PSS/PDMS-PUa/SiO2 Film with Conductive Self-Cleaning and De-Icing Functionality

by
Jie Fang
1,†,
Rongqing Dong
1,†,
Meng Zhou
2,3,*,
Lishan Liang
1,
Mingna Yang
1,
Huakun Xing
4,*,
Yongluo Qiao
5,* and
Shuai Chen
1,3,4,*
1
Jiangxi Provincial Engineering Research Center for Waterborne Coatings, School of Chemistry and Chemical Engineering, Jiangxi Science & Technology Normal University, Nanchang 330013, China
2
Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
3
Jiangxi Provincial Key Laboratory of Flexible Electronics, Flexible Electronics Innovation Institute, Jiangxi Science & Technology Normal University, Nanchang 330013, China
4
Institute of Energy Materials and Nanotechnology, School of Civil Engineering and Architecture, Nanchang Jiaotong Institute, Nanchang 330100, China
5
Jiangxi Provincial Key Laboratory of Organic Functional Molecules, Jiangxi Science & Technology Normal University, Nanchang 330013, China
*
Authors to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Coatings 2025, 15(9), 985; https://doi.org/10.3390/coatings15090985 (registering DOI)
Submission received: 30 July 2025 / Revised: 18 August 2025 / Accepted: 20 August 2025 / Published: 23 August 2025
(This article belongs to the Special Issue Advances in Electrically Conductive Coatings: Materials, Preparation and Applications)
Browse Figures
Review Reports Versions Notes

Abstract

Poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) stands out as a renowned commercial conducting polymer composite, boasting extensive and promising applications in the realm of film electronics. In this study, we have made a concerted effort to overcome the inherent drawbacks of PEDOT:PSS films (especially, high moisture absorption, mechanical damage vulnerability, insufficient substrate adhesion ability, etc.) by uniformly blending them with polydimethylsiloxane polyurea (PDMS-PUa) and silica (SiO2) nanoparticles through a feasible mechanical stirring process, which effectively harnesses the intermolecular interactions, as well as the morphological and structural characteristics, among the various components. The Si−O bonds within PDMS-PUa and the −CH3 groups attached to Si atoms significantly enhance the hydrophobicity of the composite film (as evidenced by a water contact angle of 132.89° under optimized component ratios). Meanwhile, SiO2 microscopically modifies the surface morphology, resulting in increased surface roughness. This composite film not only maintains high conductivity (1.21 S/cm, in contrast to 0.83 S/cm for the PEDOT:PSS film) but also preserves its hydrophobicity and electrical properties under rigorous conditions, including high-temperature exposure (60–200 °C), ultraviolet (UV) aging (365.0 nm, 1.32 mW/cm2), and abradability testing (2000 CW abrasive paper, drag force of approximately 0.98 N, 40 cycles). Furthermore, the film demonstrates enhanced resistance to both acidic (1 mol/L, 24 h) and alkaline (1 mol/L, 24 h) environments, along with excellent self-cleaning and de-icing capabilities (−6 °C), and satisfactory adhesion (Level 2). Notably, the dried composite film can be re-dispersed into a solution with the aid of isopropanol through simple magnetic stirring, and the sequentially coated films also exhibit good surface hydrophobicity (136.49°), equivalent to that of the pristine film. This research aims to overcome the intrinsic performance drawbacks of PEDOT:PSS-based materials, enabling them to meet the demands of complex application scenarios in the field of organic electronics while endowing them with multifunctionality.

Graphical Abstract

1. Introduction

Electrically conductive films, as special functional films mainly relying on a composition system of conductive filler, polymer substrate, and solvent, have been widely used in modern electronic industries [1,2]. In contrast to typically conductive fillers, including copper, silver, metal oxides, and others [3], in recent years, conducting polymers (CPs) have received great attention [4,5,6,7]. Among them, the film of poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), a famous commercial CP in large-scale production, attracts thousands of studies each year, accompanied by abundant uses in optoelectronics [8], biomedicine [9], flexible electronics [10], and other fields [11]. Its excellent waterborne processing, mixability, and film-forming capacities, together with intrinsic electrical conductivity, optoelectronic activity, optical transparency, thermal stability, and so on of the film, make it an ideal material in the field of conductive films [12,13]. However, although it can combine the two functions of conductive fillers and polymer matrices into one, it has serious problems, such as a high moisture absorption rate, vulnerability to mechanical damage, and insufficient matrix adhesion ability [14]. These issues should be taken seriously, and the stability and miscibility of its original water dispersion are also worthy of exploration [14,15]. To meet these challenges, cooperating with other components to form composite material dispersions and films has become one of the most popular strategies.
Previously, the synergistic interaction with other organic and inorganic components has more or less effectively addressed these issues. Promisingly, the advent of bionic electronics provides new ideas like super-hydrophobic surfaces inspired by the outstanding waterproof property with a surface water contact angle (WCA) of more than 150° for solving these problems [16,17,18]. By observing the surface structure of the lotus leaf [19], it can be seen that its microstructure with certain surface roughness is quite beneficial in preventing water droplets from adhering to the surface [20]. In other words, the synergistic effect of micro/nano-scale surface rough structure together with low surface energy chemical composition can achieve superhydrophobicity of the surface [21,22]. Up to now, there are many ways to prepare rough surfaces, such as chemical etching [23], laser etching [24], electrochemical deposition [25], vapor deposition [26], molecular self-assembly [27], template method [28], hydrothermal method [29], and so on. Surface modification is commonly performed using fluorine/silicon-containing organic compounds, long-chain alkanes, and other low-surface-energy substances to reduce the surface free energy.
To facilitate the transformation of PEDOT:PSS from hydrophilic to hydrophobic, the introduction of specific modifiers is necessary. PEDOT:PSS inherently exhibits strong hydrophilicity, primarily due to the presence of −SO3− groups in PSS [30]. To alter its surface properties, chemical modification of PEDOT:PSS is necessary to reduce or eliminate these hydrophilic groups. Commonly used methods include introducing hydrophobic groups, employing surfactants, or altering their surface energy through blending. However, current research on PEDOT:PSS aqueous solutions has found that it was difficult to alter its properties by introducing other chemical groups. Instead, most studies opt for physical blending methods to enhance the properties of PEDOT:PSS films [31,32,33]. PEDOT:PSS constitutes a water-based system, whereas the majority of hydrophobic polymers are insoluble in water. Consequently, identifying a compatible substance that can effectively impart hydrophobicity to PEDOT:PSS while maintaining its electrical capability presents a significant challenge (Table 1). For example, our group has found that, polyhedral oligomeric silsesquioxane (POSS), which has small nano size, cage structure, easy doping of polymer materials, enhanced thermal stability, surface hardening, hydrophobicity, and other properties [34], can weaken the hydrophilicity of PEDOT:PSS system and enhance its mechanical flexibility [35]. And, after the further introduction of waterborne epoxy resin and silane coupling agent, the adhesion, hardness and wear resistance of PEDOT:PSS-based film to the glass substrate can be improved by forming a much higher crosslinked network structure [36]. Additionally, in the field of solar cells, the hygroscopicity and acidity of PEDOT:PSS, when used as a hole transport layer, are key factors affecting the stability of the cells. To address this issue, Ma et al. introduced a hydrophobic perfluorosulfonic acid copolymer (Nafion) into PEDOT:PSS via a spin-coating process. The resulting composite films exhibited hydrophobicity (107°), chemical stability, and mechanical stability, leading to a marked improvement in device stability [37]. However, the hydrophobicity in this research is insufficient to support the promising uses of PEDOT:PSS-based film in fields like self-cleaning, corrosion resistance, anti-icing, anti-fogging, drag reduction, and oil–water separation [38,39], and the film durability is not studied in depth.
During the design of polydimethylsiloxane polyurea (PDMS-PUa), we introduced groups into the PDMS-PUa molecular chain that can interact with the functional groups in PEDOT:PSS. PDMS-PUa contains –NH2 functional groups, which have the potential to form hydrogen bonds with polar groups such as −SO3− in PEDOT:PSS. The PDMS component provides excellent flexibility and low surface energy, contributing to the hydrophobic properties of the film. On the other hand, the PUa component allows for the control of material hardness, toughness, and interactions with other components by adjusting its chemical composition [40]. PDMS-PUa can also coat the surface of SiO2 nanoparticles, preventing their aggregation and improving the dispersion of SiO2 nanoparticles in composite systems, which aids in the formation of a uniform film structure. SiO2 nanoparticles can serve as a physical filler in films, constructing microstructures to enhance the performance of the films. During mechanical stirring, SiO2 nanoparticles can be uniformly dispersed within the mixed system of PEDOT:PSS and PDMS-PUa. These particles can form a “scaffold”-like structure inside the film, increasing the roughness and porosity of the film. In high-temperature environments, SiO2 nanoparticles maintain their structural integrity, preventing deformation of the film due to heat. Additionally, in chemical environments, SiO2 nanoparticles can resist corrosion from chemicals such as acids and bases, protecting the conductive component PEDOT:PSS and other organic components like PDMS-PUa within the film, thereby extending its service life.
Here, in order to change the strong hydrophilicity of PEDOT:PSS to hydrophobicity, a conductive composite was designed by introducing a hydrophobic polymer and inorganic nanomaterial via simple physical blending. In detail, a hydrophobic polymer PDMS-PUa, was synthesized by using amino-terminated PDMS, which contained Si−O bonds to reduce its surface energy, and then SiO2 nanoparticles were added to increase the roughness of the film (Figure 1). The multiple functions of PEDOT:PSS/PDMS-PUa/SiO2 film are also studied, along with or beyond hydrophobicity.

2. Materials and Methods

2.1. Materials

Isophorone diisocyanate (IPDI, 99%), acetone, ethanol, dimethyl sulphoxide (DMSO), dichloromethane (DCM), SiO2 (99.5%, 30 nm) and isopropanol (IPA) were purchased from Shanghai Aladdin BioChem Technology Co., Ltd., Shanghai, China. Methanol (MeOH, 97%) were purchased from Shanghai Titan Scientific Co., Ltd., Shanghai, China. NH2-PDMS-NH2 (Mn = 2500) was purchased from Sigma-Aldrich Co., Ltd, Shanghai, China. Concentrated H2SO4 (Duksan Pure Chemicals, >95%) was purchased from Shanghai Xilong Scientific Co., Ltd., Shanghai, China. The potassium hydroxide (KOH, AR) plate was purchased from Vita Chemical Reagent Co., Ltd., Shanghai, China. Aqueous dispersion of PEDOT:PSS (CleviosTM PH1000, solid content of 1.14 wt.%, pH value of 2.01 under 25 °C, viscosity of 36 mPa∙s under 25 °C) was purchased from Germany Heraeus Electronic Materials Co., Ltd., Shanghai, China. Calcium–sodium glass (20 mm × 20 mm × 1.1 mm) was purchased from Zhuhai Kaivo Optoelectronic Technology Co., Ltd, Zhuhai, China. Polypropylene (PP) plates (20 mm × 20 mm × 3 mm) were purchased from Shanghai Vita Co., Ltd, Shanghai, China. They are made from pretreating normal glass and PP by washing them with dichloromethane, ethyl alcohol, acetone, water and ethyl alcohol.

2.2. Synthesis of PDMS-PUa

Figure S1 illustrates the synthetic route of PDMS-PUa [41]. DCM (40 mL) was injected into a 100 mL three-necked flask containing H2N-PDMS-NH2 (Mn = 2500, 10.0 g) under N2 and stirred by magnetic stirring to ensure that H2N-PDMS-NH2 is fully and uniformly dissolved in DCM. After stirring for 30 min in N2, IPDI (0.11 g/mL, 10 mL) was placed in an ice-water bath. The reaction was carried out in an ice water bath for 4 h, and then at 25 °C for 48 h. Once the reaction had reached completion, 5 mL of MeOH was added to the solution, and the resulting polymer solution was concentrated at 60 °C using a rotary evaporator. Subsequently, the resulting polymer, designated as PDMS-PUa, was subjected to drying in a blast oven at a temperature of 60 °C for a period of 12 h.

2.3. Fabrication of PEDOT:PSS/PDMS-PUa/SiO2 Films

The synthesized PDMS-PUa was dissolved in IPA solution, and the dispersions with concentrations of 10 wt.%, 20 wt.%, 30 wt.%, 40 wt.% and 50 wt.% were prepared, and magnetically stirred for 6 h. The SiO2 with a concentration of 5 wt.% was dissolved in IPA and magnetically stirred for 6 h. The above two solutions (PDMS-PUa/SiO2) were mixed in equal volume and magnetically stirred for 6 h. A total of 5% volume fraction of DMSO was added to the PEDOT:PSS (2 mL) dispersion and mechanically stirred for 30 min. Then, IPA with volume fractions of 10%, 20%, and 30% was added separately to the aforementioned PEDOT:PSS/DMSO solution, and the formed mixture PEDOT:PSS/DMSO/IPA-X (X = 10%, 20% and 30%) was mechanically stirred for 30 min. Then they were mixed with PDMS-PUa/SiO2 with the same volumes and mechanically stirred for 3 h. In total, 0.6 mL of PEDOT:PSS/PDMS-PUa/SiO2 dispersion was drop-cast onto sodium-calcium glass (2 cm × 2 cm), and then the film was prepared by vacuum drying at 60 °C for 12 h.

2.4. Characterization of PEDOT:PSS and PEDOT:PSS/PDMS-PUa/SiO2 Films

2.4.1. Structure and Morphology

Scanning electron microscopy (SEM, Regulus 8100, Hitachi, Tokyo, Japan), an atomic force microscope (AFM, Bruker Dimension Icon, Karlsruhe, Germany), and an energy dispersive spectrometer (EDS, Octane Elect Super-70 mm2, EDAX, Mahwah, NJ, USA) were used to record the surface morphology and EDS mapping (C, S, O and Si element) of these films.

2.4.2. Spectral Absorbency

The molecular structures of PEDOT:PSS/PDMS-PUa/SiO2 films were investigated using a Fourier-transform infrared (FT-IR) spectrometer (ALPHA-II, Bruker, Karlsruhe, Germany), under resolution (Δν = 0.5 cm−1), with 16 scans, and under ambient conditions of 25 ± 1 °C. The absorbance of the composite film was studied by the SPECORD 200 PLUS Ultraviolet-visible (UV-vis) spectrophotometer. The molecular structures of H2N-PDMS-NH2, PDMS-PUa, SiO2, PEDOT:PSS, and PEDOT:PSS/PDMS-PUa/SiO2 were analyzed by FT-IR spectroscopy (with the exception of H2N-PDMS-NH2, which was analyzed via attenuated total reflection (ATR) spectroscopy; others were all tested as potassium bromide (KBr) pellets).

2.4.3. Electrical Capability

Electrical conductivity: The bulk resistance (R) of the films before and after self-healing was measured using a digital multimeter (DMM 6500 SourceMeter, Keithley, Cleveland, OH, America), and the conductivity (σ) was calculated based on a formula. The films prepared in the same way are measured in parallel three times, and the conductivity (σ) is calculated to obtain the average and standard deviation. The σ can be calculated by the formula:
σ = L/(RS)
where L is the length of the film during the measured process expressed in length units cm, R is the digital multimeter value expressed in resistance units Ω, and S is the cross-sectional area of the film (S = film thickness × film width) expressed in area units cm−2. The final σ is given in units of S/cm.
The film thickness was measured by an SGC-10 film thickness meter (Tianjin Guangdong Sci. & Tech. Co., Ltd., Tianjin, China).

2.4.4. Surface Wettability

After preparing the relevant dispersions, they were cast onto soda-lime glass slides (2 cm × 2 cm). Two samples were prepared for each composition ratio. The films were then vacuum-dried at 60 °C for 12 h. The WCA of each film was measured by a contact angle goniometer to determine its surface tension (SDC-100, Dongguan Shengding Precision Instrument Co., Ltd., Dongguan, China) under ambient conditions of 25 ± 1 °C and 50% relative humidity (RH). During testing, each sample was measured at three different positions, and the average value of the test results was calculated along with the standard deviation The WCA of each film was measured by a contact angle goniometer to determine its surface tension (SDC-100, Dongguan Shengding Precision Instrument Co., Ltd., China) under ambient conditions of 25 ± 1 °C and 50% RH.

2.4.5. Surface Abradability

According to the literature, the mechanical stability of the hydrophobic film was evaluated by a self-made method [42]. The surface to be worn was formed from 2000 CW abrasive paper. The sample is subjected to a drag force equivalent to the weight of a 100 g object (approximately 0.98 N), resulting in a linear displacement of 20 cm per cycle. Following every 5 wear tests, the WCA on the film surface was quantified.

2.4.6. Interfacial Adhesion

The adhesion tests of coatings were determined according to ISO 2409-2013. The cross-cut test was performed with a blade for scribing (BGD 503 Cross Cutting Rule (1 mm gap), Biuged Instruments Co., Ltd., Guangzhou, China). The adhesion was evaluated by observing the peeling area with transparent adhesive tape adhered to the scribed area, and the results of the test were categorized into six grades from 5 to 0, where grade 0 indicates the best adhesion and grade 5 indicates the worst adhesion of the coatings. Three parallel tests were made for each coating sample, and the tape peeling time was within 0.5–1 s for each test.

2.4.7. Thermostability

The impact of temperature fluctuations on the hydrophobicity of the film was evaluated via experimentation conducted on an electric hot plate (Shanghai Lichen Bangxi Instrument Technology Co., Ltd., Shanghai, China. DB-XAB). The samples were placed at different temperatures (Heat treatment range 60–200 °C) for 2 h. Subsequently, the samples were permitted to cool naturally to room temperature. The aforementioned process may be considered a temperature change cycle. Following each temperature change cycle, the WCA and electrical conductivity of the film surface were measured.

2.4.8. UV Aging

The films were irradiated for 12 h by placing them in a triple-use UV instrument dark box with UV light (Triple-purpose ultraviolet analyzer, ZF-2, Shanghai Anting Scientific Instrument Factory, Shanghai, China) at 365.0 nm (light intensity: 1.32 mW/cm2). Aging of the films including WCA and conductivity was observed.

2.4.9. Chemical Corrosion

The composite films were immersed in KOH (1 mol/L) and H2SO4 (1 mol/L) solution for 24 h. Then the composite film after three times of immersion was rinsed with ethanol and dried in an oven at 25 °C for 1 h.

2.4.10. Contamination

The film was placed at an inclined angle, and pollutants such as dust and ink were placed on the surface. Deionized water was injected on the surface with a syringe to observe whether the pollutants remained.

2.4.11. Icing

A 5 μL deionized water droplet was dropped onto the sample surface with a syringe, followed by freezing at −6 °C. After the ice was removed, the effect on the surface of the film was observed.

2.4.12. Redispersion

The composite film was cut into small pieces, and 1mL IPA was added for magnetic stirring for 6 h. A total of 0.6 mL of redispersed solution was drop-cast onto sodium–calcium glass (2 cm × 2 cm), and then a rigid film was prepared respectively by vacuum drying at 60 °C for 12 h.

3. Results and Discussion

3.1. Structure and Morphology Analysis of PEDOT:PSS/PDMS-PUa/SiO2 Films

In this work, we first synthesized PDMS-PUa, then mixed it with SiO2 nanoparticles, and then introduced aqueous dispersion of PEDOT:PSS into this composite to prepare PEDOT:PSS/PDMS-PUa/SiO2 dispersions and their films. As shown in Figure 2a, the infrared spectroscopy of PDMS-PUa retains H2N-PDMS-NH2’s characteristic peaks (Si−O−Si at 1067 and 1013 cm−1, Si−C at 800 cm−1), showing preserved structure during synthesis. In the PDMS-PUa spectra, the N−H and C=O bending vibrations in O=C−N−H can be observed at 1570 cm−1 and 1627 cm−1, respectively, which proves that we have successfully synthesized the polymer PDMS-PUa [41]. There is a triple vibration peak of Si−C bond at 800 cm−1. Due to the chemical environment around the Si atoms in PDMS, the vibration of the Si−C bond would produce obvious absorption peaks in the FT-IR spectrum [43]. The presence of PEDOT:PSS in PEDOT:PSS/PDMS-PUa/SiO2 composite films can also be seen by the peaks at 1619 and 1408 cm−1, which are C−C and C=C stretching vibrations of the quinone structure of the thiophene ring [44]. The absorption peak located at 1174 cm−1 originates from the asymmetric and symmetric vibrations of S−O in the sulfonic acid group of the PSS chain [45].
In Figure 2b, the SEM image of PEDOT:PSS distinctly reveals a smooth surface. As the content of PDMS-PUa/SiO2 increased, the surface of the composite film exhibited a more pronounced three-dimensional structure and rough surface morphology. Since PDMS-PUa has negatively charged electrons and carbon-based (−C=O) secondary amines (−NH) can form strong hydrogen bonds, it can drive polymer molecules to uniformly nucleate [43]. During the film formation process, the higher content of the polymer would precipitate to form a single core as the solvent evaporates. When the solid content of PDMS-PUa is 10 wt.%, it forms a rough PDMS-PUa core, and the uneven shrinkage causes some pores on the surface (Figure 2c). As the content of PDMS-PUa increases, the solvent concentration gradient decreases and the pores disappear (Figure 2d,e). Figure S2 shows the results of EDS analysis of different polymer samples. It can be seen that PEDOT:PSS contains elements such as C, O, and S, with the content of the S element being the highest. In addition, the PEDOT:PSS/PDMS-PUa/SiO2 samples contain elements such as C, N, O, Si, S, and so on. The Si element is rich near point 1.7, followed by the O element, while the content of the S element is significantly lower than that of PEDOT:PSS, indicating that PDMS-PUa/SiO2 is the main component and is successfully compounded with PEDOT:PSS. And with the increase of PDMS-PUa content, the peak intensity of the Si element increases gradually. The existence of PEDOT:PSS, PDMS-PUa, and SiO2 in the same film was well proved by elemental maps (Figure 2f). In Figure 2h, it can be seen that both the horizontal and vertical axes are labeled with scales from μm to nm. The roughness of PEDOT:PSS is 1.40 nm, while the roughness of PEDOT:PSS/PDMS-PUa/SiO2 is 310 nm. Compared with the AFM images of PEDOT:PSS, PEDOT:PSS/PDMS-PUa/SiO2 exhibits a rough surface with micrometer protrusions (Figure 2g,h). The dual action of PDMS-PUa and SiO2 promotes the appearance of a rough surface that allows PEDOT:PSS to change from hydrophilic (pristine film) to hydrophobic (composite film) properties.

3.2. Optoelectronic Properties of PEDOT:PSS/PDMS-PUa/SiO2 Films

3.2.1. Color and UV-Vis Absorption Spectra

As illustrated in Figure 3a, when the IPA volume ratio is 10%, the PEDOT:PSS dispersion exhibits uniform morphology, with the highest conductivity (1.21 S/cm) and WCA (132.39°). Nevertheless, when the IPA concentration is excessively high, the film is insufficiently thick and fragile. However, when the volume ratio of IPA is lower than 10%, it leads to an uneven distribution of PEDOT-rich agglomerates in the system and insufficient conformational optimization of the PEDOT chain, thus resulting in a decrease in electrical conductivity [46]. For example, when the IPA volume ratio was 8%, the conductivity of the composite film decreased to approximately 0.9 S/cm. On the other hand, the addition of DMSO can facilitate the dispersion of the PEDOT chain and reduce the PSS wrapping between PEDOT, thereby improving the conductivity of PEDOT:PSS [47,48,49]. In this study, we chose to add 5% (v/v) DMSO to achieve the optimal conductivity, which has been widely known in this field [47]. As both PDMS-PUa and SiO2 contain Si-O bonds, they can be dispersed in IPA to form a uniform mixture and to prepare blue films. Therefore, in the following experiments, PEDOT:PSS/DMSO (5%)/IPA (10%) was selected as the object. From the UV-vis absorption spectra, it can be seen that there is a strong absorption peak near 654 nm, which is due to the dioxane group reducing the energy barrier of the polythiophene structure (Figure 3b) [50].

3.2.2. Surface Resistance and Electrical Conductivity

The raw data (length, electrical resistance, cross-sectional area) of PEDOT:PSS/PDMS-PUa/SiO2 composite membranes are shown in Table S1. Multiple parallel experiments have shown that when the solid content of PDMS-PUa is 40% by weight, the conductivity increases (17.73 S/cm). During the process of forming a composite film, PDMS-PUa naturally deposits the lower layer due to its high density (Figure 3c). Meanwhile, the proportion of PEDOT:PSS in the upper layer increases accordingly, resulting in an enhancement of the film’s conductivity. As illustrated in Figure 3d, as the PDMS-PUa content increases, the S element weight on the top surface and cross-section of the composite film decreases from 10 wt.% to 30 wt.%, before increasing again at 50 wt.%. This trend is further corroborated by the EDS intensity of the composite film (Figure 3e). The conductivity of the PEDOT:PSS film was 33.31 S/cm when DMSO and IPA were added to the PEDOT:PSS aqueous dispersion. As the PDMS-PUa content increased, the conductivity gradually decreased (Figure 4a). As shown in Figure 4b,c, the hydrophobic PEDOT:PSS/PDMS-PUa/SiO2 film acts as an interconnect to turn on the lamp underwater. The lamp continues to glow steadily, which indicates that the prepared composite film can be used as an underwater interconnector. When immersed in pure water, the hydrophobic coating on its surface acts as a barrier that blocks direct interaction between water molecules and the material’s interior, effectively shielding the conductive components from water exposure. This robust physical separation negates influence of water’s conductivity on the film’s electrical circuitry, thereby preserving its electrical insulation properties [51].

3.3. Surface-Interface Properties of PEDOT:PSS/PDMS-PUa/SiO2 Films

3.3.1. Surface Hydrophobicity

As can be seen in Figure 4d, the WCA of the PEDOT:PSS/PDMS-PUa film reaches a maximum of 104.79°. The maximum value of WCA of the PDMS-PUa film is 107.7°, and its hydrophobicity mainly originates from the Si−O bond in the main chain of PDMS, and the Si atom is connected with the −CH3 group [41,52]. To further bolster the hydrophobicity, we draw inspiration from the Lotus effect by micro- and nanostructure construction onto the surface of the composite film. And SiO2 nanoparticles, being one of the most favored nanoscale particles, are utilized to create nanoscale roughness within the coatings [33,53].
With the addition of PDMS/PUa and SiO2, the WCA of the PEDOT:PSS composite film was significantly enhanced. When the content of PDMS-PUa is 30 wt.%, the WCA of the PEDOT:PSS composite film has a maximum value of 132.89° (Figure 4a). This result initially comes from the presence of PDMS segments within PDMS-PUa, which possesses a unique chemical structure [41]. On the one hand, the backbone of PDMS, composed of Si−O bonds and with Si atoms attached to −CH3 groups, inherently endows PDMS-PUa with certain hydrophobic properties. On the other hand, the Si−O bonds are relatively long in size (0.16 nm) and with a relatively large bond angle (143°), which grants the molecular chains of PDMS-PUa excellent flexibility, enabling them to form a relatively loose structure on the film’s surface. At the same time, the −CH3 groups of PDMS-PUa are arranged outwardly, resembling “little umbrellas”, which effectively hinder the contact of water molecules and thereby enhance the hydrophobic effect. Furthermore, the nanostructure of SiO2 can alter the surface morphology of the composite film at the microscopic level [51]. These microscopic structures can increase the entrapment of air on the film’s surface, thereby enhancing its hydrophobicity continually. This phenomenon is analogous to the microscopic structure of a lotus leaf’s surface. Moreover, the Si−O bonds in PDMS-PUa can interact with the Si−O bonds on the surface of SiO2 through van der Waals forces or weaker chemical bonds, further contributing to the composite’s overall hydrophobic properties [54]. This interaction results in a tighter bonding among diverse components and also helps maintain a low surface energy state on the composite film’s surface. It can be seen from Figure S4a,b that in view of the PDMS-PUa content, the element weight and EDS intensity of Si all increase from 10 wt.% to 30 wt.% and then decrease if further to 50 wt.%. This is possibly because under PDMS-PUa (50 wt.%), the composite film was layered during its formation, resulting in the deposition of heavier PDMS-PUa components in the lower layer. Therefore, the PEDOT:PSS/PDMS-PUa/SiO2 film with a PDMS-PUa content of 30 wt.% was selected as the optimal system for further research.
Figure 4e demonstrates the wetting resistance of the composite film to various liquids. The liquids tested (red ink, milk, coffee, milk tea, and water) remained completely oval on the paper without wetting behavior, indicating good hydrophobicity. All of these substances form stable droplets on this surface, which is repellent to liquids of different properties. Hydrophilic substances have a relatively small surface WCA, usually < 90°. Compared to the water absorption of PEDOT:PSS, the PEDOT:PSS/PDMS-PUa/SiO2 film has good hydrophobicity in contact with water droplets (Figure 4f,g). This is attributed to the highly acidic and hygroscopic nature of PSS− in PEDOT:PSS, which causes the film to swell. However, during the preparation of the PEDOT:PSS composite films, the addition of DMSO stretches the PEDOT chain and removes some of the PSS, thus reducing the film’s water absorption [47,48,53].

3.3.2. Surface Abradability

In Figure 4h, the WCA of the PEDOT:PSS film exhibited hydrophilic properties even under 40 times of friction, although it showed a decreasing trend (Figure S5). With the incorporation of 30 wt.% PDMS-PUa and 5 wt.% SiO2 (mainly due to its high WCA, as shown in Figure S3), the friction resistance of the PEDOT:PSS/PDMS-PUa/SiO2 film gradually increased. After undergoing 40 times of friction, WCA remained at about 100° with a reduction percentage of 24.7% compared to the initial value of 132.89°, maintaining good hydrophobic properties, indicating that the film had some wear resistance. When subjected to 40 friction cycles, the surface structure of the composite film may undergo changes, such as an increase in surface roughness and alterations in surface chemical properties. These changes usually lead to an increase in the hydrophilicity of the film surface, because the rough surface increases the contact area between the water molecules and the film. The wear resistance of coated hydrophobic materials is crucial for the long-term maintenance of their properties. With the accumulation of wear, the conductivity of the PEDOT:PSS/PDMS-PUa/SiO2 composite film experiences a distinctive pattern of changes, initially declining, then increasing, and finally demonstrating a downward trend. Similarly, the conductivity of the PEDOT:PSS film also increased slightly and decreased. This phenomenon may be attributed to the wear of the PEDOT:PSS/PDMS-PUa/SiO2 film, which exposes a greater proportion of the conductive film to the surface. Consequently, the electrical conductivity is enhanced, leading to an increase in wear. However, as the wear progresses, the conductivity is reduced once more.

3.3.3. Interfacial Adhesion

Figure 4i shows that as the PDMS-PUa content increased, the adhesion of the film gradually increased. The reason for this is that there are abundant hydrogen bonds existing in the molecular structure of PDMS-PUa, primarily arising from interactions between the ureido groups (NH−CO−NH) in the PU segments and the carbonyl groups (C=O) or amino groups (N−H) of adjacent molecular chains. These hydrogen bonds can interact with the glass substrate to improve the adhesion of the film [55]. At the same time, the addition of SiO2 increases the surface roughness of the composite film. The rough surface provides more physical attachment sites for other materials, enabling mechanical interlocking. During the deposition process, PEDOT:PSS can fill into these rough surface structures, forming an interlocking structure that further enhances adhesion [56]. The PDMS-PUa itself also has good viscoelasticity. Although the low surface energy of PDMS may result in its lower adhesion to other materials, its flexibility helps alleviate stress and prevent the film from peeling due to stress concentration during the adhesion process [43].

3.4. Durability of the Hydrophobic PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 Films

3.4.1. Thermostability

In order to ascertain the impact of the PEDOT:PSS/PDMS-PUa/SiO2 film under extreme conditions, it was subjected to different temperatures (60–200 °C) within two hours, during which time the change in the values of WCA and conductivity was monitored (Figure 5a). With the change in temperature originating at 60 °C, the WCA of PEDOT:PSS/PDMS-PUa/SiO2 film first decreases from 119.7° to 94.5°, then increases at 120 °C, and then changes slightly. In comparison, the WCA of the PEDOT:PSS film exhibits a downward trend that is relatively stable. For this reason, as the temperature increases, the molecular chain movement of PDMS-PUa intensifies, which may result in an enlargement of the gaps between molecular chains of PEDOT:PSS/PDMS-PUa/SiO2, thereby affecting the hydrophobicity of the film to a certain extent. Furthermore, an elevation in temperature may lead to the formation of micropores or cracks within the film, affecting its surface roughness and hydrophobicity [43]. As the temperature rises, the overall conductivity of the PEDOT:PSS film shows a decreasing trend, whereas the conductivity of the PEDOT:PSS/PDMS-PUa /SiO2 composite film exhibits an initial decline followed by a subsequent increase. The elevated temperature can result in a structural rearrangement of the PEDOT:PSS film, accompanied by a rearrangement of PEDOT [57], which shrinks the PSS region and increases conductivity (1.63 S/cm).

3.4.2. Anti-UV Aging Capability

In the context of everyday life, the film is inevitably exposed to UV light when it is in contact with outdoor sunlight. Therefore, it is crucial to assess the anti-UV stability of the composite film. To determine its durability, the composite film was subjected to UV light irradiation testing. Figure 5b illustrates the alteration in WCA and conductivity. The results demonstrate that the WCA of the composite film exhibits a reduction from 132.89° to 116.55° following 12 h of irradiation. Furthermore, the WCA is observed to decrease to 96.29° after 24 h of irradiation. UV light exposure accelerates the oxidation process of materials. Under the influence of UV light, O2 molecules can react with the material’s surface to form oxides with stronger hydrophilic properties, which in turn decreases the WCA [58]. In comparison with PEDOT:PSS, the composite film continues to exhibit hydrophobic properties. The electrical conductivity of the composite film is better than that of PEDOT:PSS. The chemical changes caused by exposure to UV light led to the degradation of some thiophene rings and counterions in PEDOT-based materials [59]. These chemical changes directly affect the doping level of PEDOT and the microstructure of the polymer films. It has been discovered that incorporating nano-SiO2 into PEDOT:PSS enhances the UV ageing resistance of the composite film.

3.4.3. Resistance to Acid and Alkali Corrosion

In the process of solvent evaporation, it can release stress well and improve adhesion. To determine the durability of the PEDOT:PSS/PDMS-PUa/SiO2 film, the film was immersed in 1 mol/L KOH and H2SO4 for 24 h (Figure 5c,d). After soaking in KOH for 24 h, the adhesion of the film decreased, and the film fell off from the glass substrate. Alkali treatment reduced the oxidation level of PEDOT+ chains, and ion exchange occurred between OH− and PSS− [60]. Due to the Columbian attraction between OH− and PEDOT+ and the doping of PEDOT, the carrier concentration is reduced, and the electrical conductivity is reduced to 0.34 S/cm. The composite film was found to be foldable after alkali immersion (Figure 5c). This may be due to the reaction of the SiO2 with the OH− to form silicate, leading to significant dissolution of SiO2 during immersion, which could facilitate the release of internal stress and the reorganization of molecular chains within the film and thus reduces its rigidity [61]. PDMS, being a silicone polymer, is inherently characterized by exceptional elasticity and flexibility. Specifically, KOH may facilitate the release of internal stress and the rearrangement of molecular chains within the thin film, resulting in higher flexibility and foldability at the macroscopic level [62]. Additionally, the strongly alkaline environment of KOH may also promote the cleavage and reorganization of certain chemical bonds on the film surface, further affecting its physical properties. When immersed in a KOH solution, KOH may react with certain functional groups on the surface of the film (such as −OH groups on the SiO2 surface), generating new hydrophilic functional groups. Consequently, the hydrophobicity of the film decreases as a result of these changes [63].
When immersed in H2SO4, some of the PSS− in the composite film is dissolved and the conductivity is significantly improved (17.19 S/cm) (Figure 5d). The −SO3− on PSS can combine with H+ in an acid to transform into −SO3H. This protonation process can alter the charge distribution and conformation of the PEDOT chains. The distance between PEDOT chains may adjust due to the change in charges, making the electron transport channels more unobstructed and thus enhancing conductivity. The stacking distance and the abundance of π–π in the thiophene ring of PEDOT play a key role in improving the intragranular conductivity of the polymer [64]. The acid may clean some impurities or weakly bound substances on the surface of the composite membrane, exposing more conductive PEDOT:PSS. At the same time, it may also improve the interfacial contact between PEDOT:PSS and PDMS-PUa, as well as SiO2. In an acidic environment, some unsaturated bonds, such as double bonds, within the composite membrane may undergo addition reactions, introducing hydrophilic groups and consequently reducing hydrophobicity.

3.4.4. Self-Cleaning Capability

It is widely acknowledged that conductive films inevitably become contaminated with dust in practical applications. The self-cleaning property of a hydrophobic surface represents an effective solution to this problem. The utilization of a silicon-containing modified film endows the composite film with self-cleaning properties, thereby effectively preventing pollution. As illustrated in Figure 5e, the coated glass substrate was positioned within a Petri dish and covered with particulate pollutants at the center of the film layer. When water droplets come into contact with the surface of the hydrophobic film, they take the form of balls and roll off, effectively removing contaminants from the surface. Herein, the self-cleaning capacity of the attained hydrophobic film is evaluated through the utilization of a dye-simulating environment. As illustrated in Figure 5f, the original PEDOT:PSS was rapidly and completely wetted and contaminated by the red ink due to its hydrophilic nature. However, the film is observed to facilitate the rapid removal of the red ink, with the water droplets rolling off and leaving the surface uncontaminated (Figure 5g). The findings demonstrate that the composite film exhibits an effective self-cleaning capability.

3.4.5. De-Icing Capability

To better adapt to the cold-weather application, we simulated the change in the film under freezing conditions (−10–0 °C). The PEDOT:PSS film itself is hydrophilic and undergoes a process of swelling upon contact with a water drop, followed by condensation into ice (Figure 5h). Consequently, the film surface would be irreversibly damaged when the ice on the surface of PEDOT:PSS is removed. The PEDOT:PSS/PDMS-PUa/SiO2 film displays excellent hydrophobic properties, thereby affording effective protection to the film, as shown in Figure 5i. Once ice forms on its hydrophobic surface, the adhesion between the ice and the coating surface is much lower than that on an ordinary surface. This is because the microstructure and low surface energy characteristics of the hydrophobic surface make it difficult for the ice to adhere firmly [65]. When a relatively small external force is applied, the ice is more likely to detach from the hydrophobic surface. So, PEDOT:PSS/PDMS-PUa/SiO2 film has the potential to be applied as conductive coatings that should be working under low-temperature environments.

3.5. Redisperse Processing of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 Films

The re-dispersibility of the PEDOT:PSS/PDMS-PUa/SiO2 film offers significant advantages in terms of resource conservation, environmental protection, and economic benefits. In previous studies, it was found that dry PEDOT:PSS was challenging to solubilize and disperse in any solvent [66]. It has been demonstrated that the IPA is soluble in water and can be mixed with a variety of organic solvents [50]. The dispersion state of SiO2 and PDMS-PUa as additives in PEDOT:PSS films is contingent upon the interaction between these additives and PEDOT:PSS, as well as the preparation process employed. These additives can be present in the film as either small particles or dispersed phases. When IPA is introduced, it can facilitate the release of these particles or dispersed phases from the film through permeation and dissolution, thereby forming a dispersion system. The PEDOT:PSS/PDMS-PUa/SiO2 film was dissolved in 1 mL of IPA and stirred for 6 h to form a uniform dispersion (Figure 6). The WCA of the composite film prepared by recycling increased by 2.7%, while the electrical conductivity is observed to decrease by about 99.8%, from 1.21 S/cm to 0.0024 S/cm. This phenomenon may be attributed to the fracture of the PEDOT:PSS molecular chain during the re-dispersion process, which has the effect of reducing the conductive path and subsequently affecting conductivity. This indicates that the composite film has the potential for re-dispersing.

4. Conclusions

In summary, in order to improve the versatile applications of CP-based conductive films in practical environments, this work has developed a hydrophobic and conductive composite film of PEDOT:PSS/PDMS-PUa/SiO2, with excellent multifunctionality. The introduction of PDMS and SiO2 containing Si−O bonds in the composite system effectively weakened the hygroscopicity of the PEDOT:PSS film and enhanced its adhesion to glass substrates. Under an optimized 30 wt.% ratio of PDMS-PUa, the composite film showed good electrical conductivity (σ = 1.21 S/cm, σPEDOT:PSS = 0.83 S/cm), better water resistance (WCA = 132.89°, PEDOT:PSS film with WCA of 76.54°), durability, de-icing, and solution redispersion. Compared with the PEDOT:PSS film, the composite film has certain flame retardancy due to its Si−O bond. In the future, in order to synergistically achieve much better conductivity and transfer it to superhydrophobicity of PEDOT:PSS-based films, new material system design needs further endeavors, while other processing methods should be considered, such as spraying, electrodeposition, layer-by-layer assembly, and so on. On the other hand, considering the nature of PEDOT:PSS itself, it is more effective to remove or replace the PSS− component in view of reducing the water absorption of the film, although this way meets quite a serious challenge in practice. It is expected that the direct applications of PEDOT:PSS-based films with the strong hygroscopic resistance will be expanded from antistatic coating, plastic electronic packaging, etc., to many promising organic electronic devices such as flexible displays, sensors, and so on.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/coatings15090985/s1, Figure S1: The synthesis route of PDMS-PUa; Figure S2: The EDS analysis results of the top surface of PEDOT:PSS and its composite films; Figure S3: The influence of varying SiO2 contents on the hydrophobic properties of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 composite films; Figure S4: The effect of PDMS-PUa (wt.%) on the (a) element weights and (b) EDS intensity of Si element of the top surface of PEDOT:PSS/PDMS-PUa/SiO2 film; Figure S5: The photo of the PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film after wear testing; Table S1: The raw size and conductive data of PEDOT:PSS/PDMS-PUa/SiO2 composite films with different PDMS-PUa contents.

Author Contributions

Conceptualization, J.F., R.D., M.Z. and S.C.; Software, J.F. and R.D.; Formal analysis, J.F. and R.D.; Investigation, L.L.; Resources, M.Y., H.X. and Y.Q.; Writing—original draft, J.F. and R.D.; Writing—review & editing, M.Z. and S.C.; Supervision, M.Z., H.X., Y.Q. and S.C.; Funding acquisition, S.C. All authors have read and agreed to the published version of the manuscript.

Funding

We are grateful to the Jiangxi Educational Committee for a Postgraduate Innovation Program grant (YC2024-X25) and the Academic Development Project of TongXin Funds (grant number 2024161806) for their financial support of this work.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available from the corresponding author upon request.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Goyal, M.; Singh, K.; Bhatnagar, N. Conductive polymers: A multipurpose material for protecting coating. Prog. Org. Coat. 2024, 187, 108083. [Google Scholar] [CrossRef]
  2. Wei, J.F.; Liang, W.D.; Mao, M.Y.; Li, B.C.; Zhang, B.B.; Zhang, J.P. Impalement-resistant, mechanically stable, and anti-static superamphiphobic coatings enabled by solvent regulation and their application in anti-icing. Langmuir 2023, 40, 1109–1116. [Google Scholar] [CrossRef]
  3. Tao, B.; Cheng, L.; Wang, J.Y.; Zhang, X.L.; Liao, R.J. A review on mechanism and application of functional coatings for overhead transmission lines. Front. Mater. 2022, 9, 995290. [Google Scholar] [CrossRef]
  4. Dube, A.; Malode, S.J.; Alodhayb, A.N.; Mondal, K.; Shetti, N.P. Conducting polymer-based electrochemical sensors: Progress, challenges, and future perspectives. Talanta Open 2025, 11, 100395. [Google Scholar] [CrossRef]
  5. Khaleque, M.A.; Aly, S.A.M.; Khan, M.Z.H. Chemical and electrochemical synthesis of doped conducting polymers and their application in supercapacitors: An overview. Chem. Eng. J. 2025, 507, 160444. [Google Scholar] [CrossRef]
  6. Shahid, M.A.; Rahman, M.M.; Hossain, M.T.; Hossain, I.; Sheikh, M.S.; Rahman, M.S.; Uddin, N.; Donne, S.W.; Hoque, M.I.U. Advances in conductive polymer-based flexible electronics for multifunctional applications. J. Compos. Sci. 2025, 9, 42. [Google Scholar] [CrossRef]
  7. Gayathri, V.; Khan, T.; Gowtham, M.; Balan, R.; Sebaey, T.A. Functionalized conductive polymer composites for tissue engineering and biomedical applications—A mini review. Front. Bioeng. Biotechnol. 2025, 13, 2025. [Google Scholar] [CrossRef]
  8. Wang, Y.; Jia, S.; Zhang, Z. PEDOT and PEDOT:PSS thin-film electrodes: Patterning, modification and application in stretchable organic optoelectronic devices. J. Mater. Chem. C 2023, 11, 10435–10454. [Google Scholar] [CrossRef]
  9. Zheng, W.Q.; Wang, L.N.; Jiao, H.; Wu, Z.X.; Zhao, Q.; Lin, T.; Ma, H.D.; Zhang, Z.L.; Xu, X.Y.; Cao, J.; et al. A cost-effective, fast cooling, and efficient anti-inflammatory multilayered topological hydrogel patch for burn wound first aid. Chem. Eng. J. 2023, 455, 140553. [Google Scholar] [CrossRef]
  10. Zhang, Z.L.; Chen, G.D.; Xue, Y.; Duan, Q.F.; Liang, X.Y.; Lin, T.; Wu, Z.X.; Tan, Y.; Zhao, Q.; Zheng, W.Q.; et al. Fatigue-resistant conducting polymer hydrogels as strain sensor for underwater robotics. Adv. Funct. Mater. 2023, 33, 2305705. [Google Scholar] [CrossRef]
  11. Faruk, O.; Adak, B. Recent advances in PEDOT:PSS integrated graphene and MXene-based composites for electrochemical supercapacitor applications. Synth. Met. 2023, 297, 117384. [Google Scholar] [CrossRef]
  12. Goyal, M.; Agarwal, S.N.; Singh, K.; Bhatnaga, N. Synthesis and characterization of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) for energy storage device application. J. Appl. Polym. Sci. 2023, 140, e53830. [Google Scholar] [CrossRef]
  13. Kim, S.J.; Park, W.S.; Hwang, J.S.; Pak, N.Y.; Choi, Y.J.; Chung, D. Study on binders for preparing antistatic films of PEDOT/PSS. Appl. Chem. Eng. 2015, 26, 458–462. [Google Scholar] [CrossRef]
  14. Chen, S.; Liang, L.S.; Zhang, Y.Q.; Lin, K.W.; Yang, M.N.; Zhu, L.; Yang, X.M.; Zang, L.; Lu, B.Y. PEDOT: PSS-based electronic materials: Preparation, performance tuning, processing, applications, and future prospect. Prog. Polym. Sci. 2025, 166, 101990. [Google Scholar] [CrossRef]
  15. Lee, I.; Park, S.; Lee, Y.S.; Kim, Y.; Kang, M.H.; Yun, C. Gradual morphological change in PEDOT:PSS thin films immersed in an aqueous solution. Langmuir 2023, 39, 1600–1610. [Google Scholar] [CrossRef]
  16. Si, Y.; Dong, Z.; Jiang, L. Bioinspired designs of superhydrophobic and superhydrophilic materials. ACS Cent. Sci. 2018, 4, 1102–1112. [Google Scholar] [CrossRef]
  17. Li, H.; Duan, Y.J.; Shao, Y.L.; Ren, L.Q.; Zhang, Z.H. Advances in organic adsorption on hydrophilic hierarchical structures for bionic superhydrophobicity–from fundamentals to applications. J. Mater. Chem. A 2024, 12, 14885–14939. [Google Scholar] [CrossRef]
  18. Lin, Y.; Shen, Y.; Liu, A.; Zhu, Y.; Liu, S.; Jiang, H. Bio-inspiredly fabricating the hierarchical 3D porous structure superhydrophobic surfaces for corrosion prevention. Mater. Des. 2016, 103, 300–307. [Google Scholar] [CrossRef]
  19. Song, W.J.; Major, Z.; Guo, Y.Q.; Karsch, S.; Guo, H.B.; Ferenc, K.; Fukumoto, M.; Dingwell, D.B. Biomimetic super “silicate” phobicity and superhydrophobicity of ceramic material. Adv. Mater. Interfaces 2022, 9, 2201267. [Google Scholar] [CrossRef]
  20. Liao, X.Q.; Goh, K.L.; Liao, Y.L.; Wang, R.L.; Razaqpur, A.G. Bio-inspired super liquid-repellent membranes for membrane distillation: Mechanisms, fabrications and applications. Adv. Colloid Interface Sci. 2021, 297, 102547. [Google Scholar] [CrossRef] [PubMed]
  21. Zhang, W.L.; Wang, D.H.; Sun, Z.N.; Song, J.N.; Deng, X. Robust superhydrophobicity: Mechanisms and strategies. Chem. Soc. Rev. 2021, 50, 4031–4061. [Google Scholar] [CrossRef] [PubMed]
  22. Zhan, Y.L.; Li, W.; Amirfazli, A.; Yu, S. Recent advances in shape memory superhydrophobic surfaces: Concepts, mechanism, classification, applications and challenges. Polymer 2022, 256, 125193. [Google Scholar] [CrossRef]
  23. Zhang, M.; Fan, J.; Li, H. Robust superhydrophobic surface with excellent corrosion resistance based on wet chemical etching method. Surf. Interfaces 2025, 64, 106363. [Google Scholar] [CrossRef]
  24. Wang, Q.; Xu, S.S.; Xing, X.T.; Wang, N. Progress in fabrication and applications of micro/nanostructured superhydrophobic surfaces. Surf. Innov. 2021, 10, 89–110. [Google Scholar] [CrossRef]
  25. Ren, Z.C.; Liu, M.M.; Yan, P.C.; Hou, Y.Y.; Wu, Y.L.; Zheng, H.Y. Laser texture-electrochemical deposition composite preparation of superhydrophobic L-Al@Ni-SA with anti/de-icing property. Surf. Interfaces 2025, 69, 106778. [Google Scholar] [CrossRef]
  26. Chang, Y.M.; Wang, Y.S.; Chen, H.Y. Controlling superhydrophobicity on complex substrates based on a vapor-phase sublimation and deposition polymerization. ACS Appl. Mater. Interfaces 2023, 15, 48754–48763. [Google Scholar] [CrossRef]
  27. Li, J.Q.; Han, X.; Li, W.; Yang, L.; Li, X.; Wang, L.Q. Nature-inspired reentrant surfaces. Prog. Mater. Sci. 2023, 133, 101064. [Google Scholar] [CrossRef]
  28. Wan, T.; Wang, B.; Han, Q.; Chen, J.S.; Li, B.C.; Wei, S.C. A review of superhydrophobic shape-memory polymers: Preparation, activation, and applications. Appl. Mater. Today 2022, 29, 101665. [Google Scholar] [CrossRef]
  29. Xu, S.S.; Wang, Q.; Wang, N. Chemical fabrication strategies for achieving bioinspired superhydrophobic surfaces with micro and nanostructures: A review. Adv. Eng. Mater. 2021, 23, 2001083. [Google Scholar] [CrossRef]
  30. Oechsle, A.L.; Schöner, T.; Geiger, C.; Tu, S.; Wang, P.; Cubitt, R.; Müller-Buschbaum, P. Unraveling the humidity influence on the electrical properties of ionic liquid posttreated poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) films. Macromolecules 2023, 56, 9117–9126. [Google Scholar] [CrossRef]
  31. Zhao, B.H.; Li, Z.; Zheng, L.; Ye, Z.C.; Yuan, Y.Y.; Zhang, S.S.; Liang, B.; Li, T.Y. Recent progress in the biomedical application of PEDOT:PSS hydrogels. Chinese Chem. Lett. 2024, 35, 109810. [Google Scholar] [CrossRef]
  32. Fung, D.D.; Qiao, L.; Choy, W.C.; Wang, C.D.; Sha, W.E.I.; Xie, F.X.; He, S.l. Optical and electrical properties of efficiency enhanced polymer solar cells with Au nanoparticles in a PEDOT:PSS layer. J. Mater. Chem. 2011, 21, 16349–16356. [Google Scholar] [CrossRef]
  33. Li, W.; Li, Y.; Song, Z.; Wang, Y.X.; Hu, W. PEDOT-based stretchable optoelectronic materials and devices for bioelectronic interfaces. Chem. Soc. Rev. 2024, 53, 10575. [Google Scholar] [CrossRef] [PubMed]
  34. Cobos, M.; Ramos, J.R.; Guzmán, D.J.; Fernández, M.D.; Fernández, M.J. PCL/POSS nanocomposites: Effect of POSS derivative and preparation method on morphology and properties. Polymer 2018, 11, 33. [Google Scholar] [CrossRef] [PubMed]
  35. Xin, X.; Yu, J.R.; Gao, N.; Xie, X.W.; Chen, S.; Zhong, J.; Xu, J.K. Effects of POSS composition on PEDOT:PSS conductive film. Synth. Met. 2021, 282, 116947. [Google Scholar] [CrossRef]
  36. Li, Z.Q.; Xie, X.W.; Zhou, M.; Zhu, L.; Fu, C.Q.; Chen, S. High water-stable, hard and strong-adhesive antistatic films from waterborne PEDOT:PSS composites. Synth. Met. 2023, 293, 117290. [Google Scholar] [CrossRef]
  37. Ma, S.; Qiao, W.; Cheng, T. Optical–electrical–chemical engineering of PEDOT:PSS by incorporation of hydrophobic nafion for efficient and stable perovskite solar cells. ACS Appl. Mater. Interfaces 2018, 10, 3902–3911. [Google Scholar] [CrossRef]
  38. Fan, X.; Nie, W.Y.; Tsai, H.; Wang, N.X.; Huang, H.H.; Xia, Y.G. PEDOT:PSS for flexible and stretchable electronics: Modifications, strategies, and applications. Adv. Sci. 2019, 6, 1900813. [Google Scholar] [CrossRef]
  39. Zhang, C.; Zhang, X.; Shen, H.; Shuai, D.C.; Xiong, X.Y.; Wang, Y.; Huang, H.J.; Li, Y. Superior self-cleaning surfaces via the synergy of superhydrophobicity and photocatalytic activity: Principles, synthesis, properties, and applications. J. Clean. Prod. 2023, 428, 139430. [Google Scholar] [CrossRef]
  40. Xie, Q.Y.; Liu, C.; Lin, X.B.; Ma, C.F.; Zhang, G.Z. Nanodiamond reinforced poly(dimethylsiloxane)-based polyurea with self-healing ability for fouling release coating. ACS Appl. Polym. Mater. 2020, 2, 3181–3188. [Google Scholar] [CrossRef]
  41. Fu, Y.H.; Xu, F.C.; Weng, D.H.; Li, X.; Li, Y.; Sun, J.Q. Superhydrophobic foams with chemical-and mechanical-damage-healing abilities enabled by self-healing polymers. ACS Appl. Mater. Interfaces 2019, 11, 37285–37294. [Google Scholar] [CrossRef]
  42. Wang, F.J.; Xie, T.X.; Ou, J.F.; Xue, M.S.; Li, W. Cement based superhydrophobic coating with excellent robustness and solar reflective ability. J. Alloy. Compo. 2020, 823, 153702. [Google Scholar] [CrossRef]
  43. Zhang, Y.; Wang, T.; Si, H.F.; Liu, Y. Superhydrophobic polyurea coating with excellent adhesion and abrasion resistance prepared via convenient microphase separation. Prog. Org. Coat. 2022, 170, 106994. [Google Scholar] [CrossRef]
  44. Du, H.; Zhang, M.; Liu, K.; Parit, M.; Jiang, Z.; Zhang, X.; Li, B.; Si, C. Conductive PEDOT:PSS/cellulose nanofibril paper electrodes for flexible supercapacitors with superior areal capacitance and cycling stability. Chem. Eng. J. 2022, 428, 131994. [Google Scholar] [CrossRef]
  45. Eshaghi, A. Fabrication of transparent silica-silica nanotube/PFTS nano-composite thin films with superhydrophobic, oleophobic, self-cleaning and anti-icing properties. Opt. Quant. Electron. 2020, 52, 516. [Google Scholar] [CrossRef]
  46. Abdel-Fattah, T.M.; Younes, E.M.; Namkoong, G.; El-Maghraby, E.M.; Elsayed, A.H.; Abo Elazm, A.H. Solvents effects on the hole transport layer in organic solar cells performance. Sol. Energy 2016, 137, 337–343. [Google Scholar] [CrossRef]
  47. Mahato, S.; Puigdollers, J.; Voz, C.; Mukhopadhyay, M.; Mukherjee, M.; Hazra, S. Near 5% DMSO is the best: A structural investigation of PEDOT:PSS thin films with strong emphasis on surface and interface for hybrid solar cell. Appl. Surf. Sci. 2020, 499, 143967. [Google Scholar] [CrossRef]
  48. Tounakti, C.; Decorse, P.; Kouki, F.; Philippe, L. Relationship between enhancement of PEDOT:PSS conductivity by solvent treatment and PSS chain reorganization. J. Polym. Sci. 2023, 61, 582–603. [Google Scholar] [CrossRef]
  49. Chou, T.R.; Chen, S.H.; Chiang, Y.T.; Lin, Y.T.; Chao, C.Y. Highly conductive PEDOT: PSS films by post-treatment with dimethyl sulfoxide for ITO-free liquid crystal display. J. Mater. Chem. C 2015, 3, 3760–3766. [Google Scholar] [CrossRef]
  50. Lattach, Y.; Deniset-Besseau, A.; Guigner, J.M.; Remita, S. Radiation chemistry as an alternative way for the synthesis of PEDOT conducting polymers under “soft” conditions. Radiat. Phys. Chem. 2013, 82, 44–53. [Google Scholar] [CrossRef]
  51. Ahmad, D.; Van Den Boogaert, I.; Miller, J.; Presswell, R.; Jouhara, H. Hydrophilic and hydrophobic materials and their applications. Energy Sources Part A 2018, 40, 2686–2725. [Google Scholar] [CrossRef]
  52. Neves, L.B.; Afonso, I.S.; Nobrega, G.; Barbosa, L.G.; Lima, R.A.; Ribeiro, J.E. A review of methods to modify the PDMS surface wettability and their applications. Micromachines 2024, 15, 670. [Google Scholar] [CrossRef]
  53. Shi, H.; Liu, C.; Jiang, Q.; Xu, J. Effective approaches to improve the electrical conductivity of PEDOT: PSS: A review. Adv. Electron. Mater. 2015, 1, 1500017. [Google Scholar] [CrossRef]
  54. Sharma, K.; Hooda, A.; Goyat, M.S.; Rai, R.; Mittal, A. A review on challenges, recent progress and applications of silica nanoparticles based superhydrophobic coatings. Ceram. Int. 2022, 48, 5922–5938. [Google Scholar] [CrossRef]
  55. Wang, D.; Yang, K.; Cheng, S. Harsh environment resistible and recyclable thermoplastic polyurea adhesivebased on stable and density hydrogen bonds. Chem. Eng. J. 2024, 482, 148663. [Google Scholar] [CrossRef]
  56. Liu, C.; Xie, Q.Y.; Ma, C.F.; Zhang, G.Z. Fouling release property of polydimethylsiloxane-based polyurea with improved adhesion to substrate. IEC Res. 2016, 55, 6671–6676. [Google Scholar]
  57. Vitoratos, E.; Sakkopoulos, S.; Dalas, E.; Paliatsas, N.; Karageorgopoulos, D. Thermal degradation mechanisms of PEDOT:PSS. Org. Electron. 2009, 10, 61–66. [Google Scholar] [CrossRef]
  58. Smoleń, J.; Stępień, K.; Mrowiec, A.; Mendala, B.; Wilczyńska, W.; Czakiert, J.; Kozioł, M. Study of resin coating adhesion on GFRP laminate surfaces after UV degradation. Int. J. Adhes. 2024, 135, 103841. [Google Scholar] [CrossRef]
  59. Schultheiss, A.; Gueye, M.; Carella, A.; Benayad, A.; Pouget, S.; Faure-Vincent, J.; Demadrille, R.; Revaux, A.; Simonato, J.P. Insight into the degradation mechanisms of highly conductive poly(3,4-ethylenedioxythiophene) thin films. ACS Appl. Polym. Mater. 2020, 2, 2686–2695. [Google Scholar] [CrossRef]
  60. Fan, Z.; Li, P.C.; Du, D.H.; Ouyang, J.Y. Significantly enhanced thermoelectric properties of PEDOT:PSS films through sequential post-treatments with common acids and bases. Adv. Energy Mater. 2017, 7, 1602116. [Google Scholar] [CrossRef]
  61. He, S.H.; Chen, J.R.; Lu, Y.; Huang, S.; Feng, K. Enhanced waterproof performance of superhydrophobic SiO2/PDMS coating. Prog. Org. Coat. 2024, 197, 108845. [Google Scholar] [CrossRef]
  62. Park, J.; Jang, J.G.; Kang, K.; Kim, S.H.; Kwak, J. High thermoelectric performance in solution-processed semicrystalline PEDOT:PSS films by strong acid-base treatment: Limitations and potential. Adv. Sci. 2024, 11, 2308368. [Google Scholar] [CrossRef]
  63. Chen, B.X.; Sun, J.P. A radiative cooling, anti-corrosion multifunctional composite coating derived from Jatropha (Jatropha curcas L.) oil. Polym. Eng. Sci. 2022, 62, 3652–3661. [Google Scholar] [CrossRef]
  64. Hosseini, E.; Kollath, V.O.; Karan, K. The key mechanism of conductivity in PEDOT:PSS thin films exposed by anomalous conduction behaviour upon solvent-doping and sulfuric acid post-treatment. J. Mater. Chem. C 2020, 8, 3982–3990. [Google Scholar] [CrossRef]
  65. Wu, B.; Cui, X.; Jiang, H.; Wu, N.; Peng, C.; Hu, Z.; Liang, X.; Yan, Y.; Huang, J.; Li, D. A superhydrophobic coating harvesting mechanical robustness, passive anti-icing and active de-icing performances. J. Colloid Interface Sci. 2021, 590, 301–310. [Google Scholar] [CrossRef] [PubMed]
  66. Xin, X.; Yu, J.; Gao, N.; Xue, Z.; Zhang, W.; Xu, J.; Chen, S. Freeze-drying and mechanical redispersion of aqueous PEDOT:PSS. J. Appl. Polym. Sci. 2020, 138, e49774. [Google Scholar] [CrossRef]
Coatings 15 00985 g001
Figure 1. Schematic diagram of the preparation process of PEDOT:PSS/PDMS-PUa/SiO2 film.
Figure 1. Schematic diagram of the preparation process of PEDOT:PSS/PDMS-PUa/SiO2 film.
Coatings 15 00985 g001
Coatings 15 00985 g002
Figure 2. (a) The FT-IR spectra of H2N-PDMS-NH2, PDMS-PUa, SiO2, pristine PEDOT:PSS, PEDOT:PSS/PDMS-PUa, and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (b) The SEM images of the films of PEDOT:PSS; (c) PEDOT:PSS/PDMS-PUa (10 wt.%)/SiO2; (d) PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2; (e) PEDOT:PSS/PDMS-PUa (50 wt.%)/SiO2; (f) The element maps of C, O, S, and Si for PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (g) The AFM images of the films of PEDOT:PSS; (h) The AFM images of the films of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2.
Figure 2. (a) The FT-IR spectra of H2N-PDMS-NH2, PDMS-PUa, SiO2, pristine PEDOT:PSS, PEDOT:PSS/PDMS-PUa, and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (b) The SEM images of the films of PEDOT:PSS; (c) PEDOT:PSS/PDMS-PUa (10 wt.%)/SiO2; (d) PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2; (e) PEDOT:PSS/PDMS-PUa (50 wt.%)/SiO2; (f) The element maps of C, O, S, and Si for PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (g) The AFM images of the films of PEDOT:PSS; (h) The AFM images of the films of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2.
Coatings 15 00985 g002
Coatings 15 00985 g003
Figure 3. (a) The effect of IPA on the conductivity and WCA of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film, with images of (b) UV-vis absorption spectrum. (c) The SEM images of the cross-section of PEDOT:PSS/PDMS-PUa (50 wt.%)/SiO2 film. (d) The influence of PDMS-PUa (wt.%) on the elemental weight of S on the top surface and cross-section of PEDOT:PSS/PDMS-PUa/SiO2 films, and (e) its impact on EDS intensity.
Figure 3. (a) The effect of IPA on the conductivity and WCA of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film, with images of (b) UV-vis absorption spectrum. (c) The SEM images of the cross-section of PEDOT:PSS/PDMS-PUa (50 wt.%)/SiO2 film. (d) The influence of PDMS-PUa (wt.%) on the elemental weight of S on the top surface and cross-section of PEDOT:PSS/PDMS-PUa/SiO2 films, and (e) its impact on EDS intensity.
Coatings 15 00985 g003
Coatings 15 00985 g004
Figure 4. (a) The effect of PDMS-PUa content on the conductivity and WCA of the PEDOT:PSS and its composite films. Conductivity of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film as an interconnector (b) in air and (c) under water. (d) The effect of PDMS-PUa contents on the WCA of PEDOT:PSS/PDMS-PUa films. (e) Photograph displaying different droplets on PEDOT:PSS/PDMS-PUa/SiO2 (30 wt.%) film. Water droplets touching (f) PEDOT:PSS and (g) PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (h) The effect of abrasion resistance test change on WCA and conductivity of PEDOT:PSS and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (i) The changes of adhesion of PEDOT:PSS and its composite films.
Figure 4. (a) The effect of PDMS-PUa content on the conductivity and WCA of the PEDOT:PSS and its composite films. Conductivity of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film as an interconnector (b) in air and (c) under water. (d) The effect of PDMS-PUa contents on the WCA of PEDOT:PSS/PDMS-PUa films. (e) Photograph displaying different droplets on PEDOT:PSS/PDMS-PUa/SiO2 (30 wt.%) film. Water droplets touching (f) PEDOT:PSS and (g) PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (h) The effect of abrasion resistance test change on WCA and conductivity of PEDOT:PSS and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. (i) The changes of adhesion of PEDOT:PSS and its composite films.
Coatings 15 00985 g004
Coatings 15 00985 g005
Figure 5. The effect of (a) temperature, and (b) UV light exposure time change on the WCA and conductivity of the PEDOT:PSS and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 films. The change of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film under (c) alkaline and (d) acidic solution after immersion for 24 h. (e) Self-cleaning tests of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. Variation in ink flow rates for PEDOT:PSS (f) and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 (g). De-icing performance of PEDOT:PSS film (h) and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 films (i).
Figure 5. The effect of (a) temperature, and (b) UV light exposure time change on the WCA and conductivity of the PEDOT:PSS and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 films. The change of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film under (c) alkaline and (d) acidic solution after immersion for 24 h. (e) Self-cleaning tests of PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 film. Variation in ink flow rates for PEDOT:PSS (f) and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 (g). De-icing performance of PEDOT:PSS film (h) and PEDOT:PSS/PDMS-PUa (30 wt.%)/SiO2 films (i).
Coatings 15 00985 g005
Coatings 15 00985 g006
Figure 6. Photos showing the re-dispersing process of PEDOT:PSS/PDMS-PUa/SiO2 film.
Figure 6. Photos showing the re-dispersing process of PEDOT:PSS/PDMS-PUa/SiO2 film.
Coatings 15 00985 g006
Table 1. Study on the hydrophobicity of PEDOT:PSS-based films.
Table 1. Study on the hydrophobicity of PEDOT:PSS-based films.
MaterialConductivityWCAApplicationRef.
PEDOT:PSS/POSS0.402 S/cm79°Antistatic Films[35]
PEDOT:PSS/Epoxy/POSS/SCA10−4 S/cm87°Antistatic Films[36]
PEDOT:PSS-Nafion/107°Solar Cells[37]
This Work1.21 S/cm132.89°Hydrophobic Coating/
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Fang, J.; Dong, R.; Zhou, M.; Liang, L.; Yang, M.; Xing, H.; Qiao, Y.; Chen, S. Hydrophobic, Durable, and Reprocessable PEDOT:PSS/PDMS-PUa/SiO2 Film with Conductive Self-Cleaning and De-Icing Functionality. Coatings 2025, 15, 985. https://doi.org/10.3390/coatings15090985

AMA Style

Fang J, Dong R, Zhou M, Liang L, Yang M, Xing H, Qiao Y, Chen S. Hydrophobic, Durable, and Reprocessable PEDOT:PSS/PDMS-PUa/SiO2 Film with Conductive Self-Cleaning and De-Icing Functionality. Coatings. 2025; 15(9):985. https://doi.org/10.3390/coatings15090985

Chicago/Turabian Style

Fang, Jie, Rongqing Dong, Meng Zhou, Lishan Liang, Mingna Yang, Huakun Xing, Yongluo Qiao, and Shuai Chen. 2025. "Hydrophobic, Durable, and Reprocessable PEDOT:PSS/PDMS-PUa/SiO2 Film with Conductive Self-Cleaning and De-Icing Functionality" Coatings 15, no. 9: 985. https://doi.org/10.3390/coatings15090985

APA Style

Fang, J., Dong, R., Zhou, M., Liang, L., Yang, M., Xing, H., Qiao, Y., & Chen, S. (2025). Hydrophobic, Durable, and Reprocessable PEDOT:PSS/PDMS-PUa/SiO2 Film with Conductive Self-Cleaning and De-Icing Functionality. Coatings, 15(9), 985. https://doi.org/10.3390/coatings15090985

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Article metric data becomes available approximately 24 hours after publication online.
Back to TopTop