Next Article in Journal
CHA-Type Zeolite Prepared by Interzeolite Conversion Method Using FAU and LTL-Type Zeolite: Effect of the Raw Materials on the Crystallization Mechanism, and Physicochemical and Catalytic Properties
Next Article in Special Issue
Visible-Light Photocatalytic Degradation of Aniline Blue by Stainless-Steel Foam Coated with TiO2 Grafted with Anthocyanins from a Maqui-Blackberry System
Previous Article in Journal
Mono vs. Difunctional Coumarin as Photoinitiators in Photocomposite Synthesis and 3D Printing
Previous Article in Special Issue
Exploring the Photothermo-Catalytic Performance of Brookite TiO2-CeO2 Composites
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Catalysts
Volume 10
Issue 10
10.3390/catal10101203
catalysts-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Large-Area Patterning of Oil-Based Inks on Superhydrophobic TiO2 Nanotubular Layers by Photocatalytic Wettability Conversion

by
Jiao Jin
,
Huihui Ren
and
Zhaoyue Liu
*
School of Chemistry, Beihang University, Beijing 100191, China
*
Author to whom correspondence should be addressed.
Catalysts 2020, 10(10), 1203; https://doi.org/10.3390/catal10101203
Submission received: 18 September 2020 / Revised: 10 October 2020 / Accepted: 13 October 2020 / Published: 17 October 2020
(This article belongs to the Special Issue Recent Advances in TiO2 Photocatalysts)
Browse Figures
Versions Notes

Abstract

:
Patterning an oil-based ink on a solid surface based on a wettability difference is of significant importance for the application of offset printing. Herein, we describe a large-area patterning of oil-based ink on a self-organized TiO2 nanotubular layer based on a photocatalytic wettability conversion. The TiO2 nanotubular layer was fabricated by electrochemical anodization, which demonstrated a superhydrophobic wettability after modification with a self-assembled molecular layer. Subsequently, area-selective ultraviolet (UV) irradiation through a pre-designed pattern of water-based UV-resistant ink formed by an ink-jet technique was used to form a wettability difference. After removing the water-based ink, an oil-based ink was capable of depositing selectively on the superhydrophobic area to form the same pattern as the pre-designed pattern of water-based ink. This large-area patterning of an oil-based ink based on the photocatalytic wettability conversion is potentially applicable in offset printing.

1. Introduction

The creation of a wettability difference on a solid surface has attracted significant attention for practical applications [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23]. One of the applications is to use the wettability difference to pattern an oil-based ink on a solid surface for offset printing [21,22,23]. Titanium oxide (TiO2) is one of the most important materials for fabricating a wettability difference [15,16,17,18,19,20,21,22,23]. A rough TiO2 surface, which typically exhibits superhydrophilicity [24,25,26], can be converted to be superhydrophobic through the modification of self-assembled molecular layers (SAMs) with a low surface free energy [27,28]. The photocatalysis of TiO2 under ultraviolet (UV) irradiation is capable of decomposing the SAMs, which achieves a photocatalytic wettability conversion of the TiO2 surface from superhydrophobicity to superhydrophilicity [15,16,17,18,19,20,21,22,27,28]. Therefore, area-selective UV irradiation through a photomask on a SAMs-modified superhydrophobic TiO2 surface can be used to fabricate a wettability difference.
The patterning of oil-based inks on a TiO2 surface with a wettability difference exhibited a promising potentiality for offset printing [21,22,23]. Compared with the conventional wettability difference between hydrophobicity and hydrophilicity on an aluminum plate based on a photosensitive polymer coating for offset printing [22,29], the wettability difference on the TiO2 surface demonstrated several advantages, such as the reusability, environmental friendship and a large wettability contrast. Nishimoto et al. described the patterning of oil-based inks on a TiO2-coated aluminum plate with a wettability difference between superhydrophobicity and superhydrophilicity for offset printing [21]. Nakata et al. prepared the patterns of oil-based inks on a rough TiO2 substrate by annealing etched Ti metal in a concentrated sulfuric acid for use as a printing plate in offset printing [22]. However, for the future application of offset printing, the fabrication of a large-area pattern of oil-based inks on a superhydrophobic TiO2 film, specifically attached to the substrate with a robust surface wettability and a low environmental cost, is very necessary.
The self-organized TiO2 nanotubular layer on Ti metal can be fabricated by a facile electrochemical anodization technique in a fluoride-contained electrolyte [30,31,32,33]. The anodization strategy is time-saving without the use of a concentrated acid, which is a versatile technique to form a TiO2 nanotubular layer on any Ti metal independent of its geometry and size [34,35]. After being modified with SAMs with a low surface free energy, the TiO2 nanotubular layer demonstrated a superhydrophobic wettability [15,36,37,38,39]. Moreover, a TiO2 nanotubular layer generally demonstrates a higher photocatalytic activity when compared with a TiO2 nanoparticular film [40], which is favorable for the photocatalytic wettability conversion. Herein, we reported the fabrication of a wettability difference on a large area TiO2 nanotubular layer by selectively decomposing the self-assembled molecular layers under ultraviolet irradiation, using a pre-designed pattern of water-based UV-resistant ink as a photomask. After removing the water-based ink, the oil-based ink was able to deposit selectively on the superhydrophobic area to form the same pattern as the pre-designed pattern of water-based ink.

2. Results and Discussion

The process for the large-area patterning of oil-based ink on a TiO2 nanotubular layer is summarized in Scheme 1. A large-area TiO2 nanotubular layer with a crystallization of anatase phase was first formed on Ti metal by electrochemical anodization (Step 1). After modification with octadecyltrimethoxysilane (ODS) self-assembled molecular layers (SAMs), a superhydrophobic surface was obtained (Step 2). Then, a pre-designed pattern of water-based ink was formed on the superhydrophobic surface by an ink-jet technique, which functioned as a UV-resistant photomask (Step 3). Under UV irradiation, the ODS SAMs that were not covered by the water-based ink were photocatalytically decomposed, which converted the surface to be superhydrophilic (Step 4). The surface that was covered by the water-based ink remained to be superhydrophobic. After the water-based ink pattern was removed by water washing (Step 5), an oil-based ink was deposited selectively on the superhydrophobic area (Step 6), which developed a corresponding pattern the same as the pre-designed pattern of water-based ink.
The electrochemical anodization is a versatile technique to form a TiO2 nanotubular layer on any Ti metal independent of its geometry and size. Compared with the conventional dip-coating and thermal calcination technique, electrochemical anodization can be used facilely to prepare a large-area and uniform TiO2 layer specifically attached to Ti metal because electrochemical anodization occurs at a solid-liquid interface using Ti metal as the precursor of TiO2. Figure 1A shows a representative photograph of a large-area TiO2 nanotubular layer (around 10 × 10 cm) prepared by anodizing a Ti sheet in a 0.5% HF solution, followed by calcination under ambient air. An oxide surface with a uniform visible color was obtained. The SEM images (Figure 1B,C) indicate that the oxide surface showed a clear nanotubular configuration with a tube internal diameter of ~87 nm, a wall thickness of ~18 nm and a tube length of ~228 nm. The nanotubular morphology significantly increased the occupied fraction of air pockets on the entire surface, which was considered to be of prime importance to achieve a superhydrophobic surface. The XRD investigation identified the anatase phase existed in the TiO2 nanotubular layer, as evidenced by the diffraction peak of anatase (101) crystal face at 2θ = 25.0° (Figure 1D).
The TiO2 nanotubular layer was further analyzed by atomic force microscope (AFM) measurement. As shown in Figure 2A, the AFM image also revealed the porous surface of a TiO2 nanotubular layer. The Root Mean Square (RMS) roughness was determined to be ~10.3 nm based on a scanning range of 1.0 × 1.0 μm. Figure 2B shows the static water contact angle (CA) of the as-prepared TiO2 nanotubular layer, which demonstrated superhydrophilicity because of the high roughness resulting from the porous surface [41]. After being modified with ODS SAMs, the TiO2 nanotubular layer showed a superhydrophobic state with a static water CA of ~156° (Figure 2C). The relation between the apparent water CA (θ′) of a composite surface with two phases of solid and gas, and the water CA (θ) of a smooth surface with one phase of solid, can be described by the Cassier equation as follows [42,43,44]:
cos θ ′ = f 1 cos θ − f 2
Herein, f1 is the fraction of the solid/water interface and f2 is the fraction of the gas/water interface, respectively, with a prerequisite of f1 + f2 = 1. Based on this equation, the large fraction (f2) of the gas/water interface in the TiO2 nanotubular layer contributed to this large water CA.
The reusability of the HF electrolyte during the electrochemical anodization is important from the standpoint of reducing the environmental cost in a practical process. We fabricated six samples with a size of around 10 × 10 cm containing a TiO2 nanotubular layer in one HF electrolyte successively. As shown in Figure 2D, after modification with ODS SAMs, all of the samples demonstrated an almost constant static water CA of ~160°, which indicated that electrochemical anodization could be used for the large-area fabrication of a TiO2 nanotubular layer for a superhydrophobic surface in a practical process.
It has been well-known that the photocatalysis of TiO2 under UV irradiation can decompose the ODS SAMs, which converts the superhydrophobic ODS-modified TiO2 nanotubular layer to be superhydrophilic. Figure 3 depicts the evolution of the static water CAs of the ODS SAMs-modified TiO2 nanotubular layer under UV irradiation. A series of water CAs were obtained between ~156° and ~0°, which was dependent on the time of UV irradiation. After UV irradiation for enough time, the superhydrophobic TiO2 nanotubular layer with a CA of ~156° could be converted to be superhydrophilic with a CA of ~0°, indicating that almost all the long-chain alkyls of ODS were decomposed by TiO2 photocatalysis and removed from the surface of TiO2 nanotubes. Two possible pathways are proposed for the photocatalytic oxidation of ODS molecules on the surface of TiO2 nanotubes [45,46,47]. Firstly, the photo-generated holes in TiO2 nanotubes can oxidize the long-chain alkyls in ODS molecules directly. Secondly, the trap of photogenerated electrons and holes by the oxygen and H2O in the surroundings under UV irradiation generates some active oxygen species, such as hydroxyl radicals (OH•), superoxide anions (O2-•) and hydrogen peroxide (H2O2), which also contributes to the oxidation of the long-chain alkyls in ODS molecules. Based on this special characteristic of UV-induced wettability conversion, area-selective UV irradiation through a pre-designed photomask on the superhydrophobic TiO2 nanotubular layer can be used to fabricate the wettability difference between superhydrophobicity and superhydrophilicity.
The pre-designed pattern of water-based ink on the superhydrophobic TiO2 surface formed by an ink-jet technique was a highly effective photomask to fabricate the wettability difference between superhydrophobicity and superhydrophilicity [21,22]. This water-based ink has a low surface free energy, which therefore can spread over the superhydrophobic TiO2 surface. Moreover, the water-based ink is able to absorb UV light, which can function as a UV-resistant film [22]. As shown in Figure 4A, a pre-designed pattern of water-based ink with a resolution of 133 lpi (lines per inch) was formed on the surface of a superhydrophobic TiO2 nanotubular layer by an ink-jet technique, which functioned as a photomask. The pre-designed pattern included some numbers, lines and areas. The morphologies of the lines with and without ink were imaged with an optical microscope (Figure 4B). A clear boundary between the TiO2 nanotubular substrate and ink was observed, indicating that the TiO2 nanotubular layer could be used as a substrate for the large-area patterning of water-based ink. Subsequently, the surface with a pre-designed pattern was illuminated by UV light. The ODS SAMs that were not covered by the water-based ink were photocatalytically decomposed, which converted the surface to be superhydrophilic, as shown in Figure 3. On the contrary, the surface that was covered by the water-based ink remained to be superhydrophobic because of the highly effective absorption of UV light. As a result, a wettability difference between superhydrophobicity and superhydrophilicity was formed on the TiO2 nanotubular layer after UV irradiation.
In order to check the preliminary application of the wettability difference on the TiO2 nanotubular layer as a printing plate for the offset printing, the water-based ink patterns were removed by water washing. Subsequently, an oil-based ink was deposited on the same surface by a hand roller. As shown in Figure 4C, the oil-based ink was able to selectively deposit on the superhydrophobic area, which developed a corresponding pattern the same as the pre-designed pattern of water-based ink. This result indicated clearly that the large-area TiO2 nanotubular layer derived from electrochemical anodization could be applied as a substrate for the patterning of oil-based ink.

3. Materials and Methods

3.1. Fabrication of a Large-Area Superhydrophobic TiO2 Nanotubular Layer

A large-area TiO2 nanotubular layer on Ti metal was prepared following our previous method with a slight change [33,40]. Briefly, a large-area Ti foil, with a size of around 10 × 10 cm (Nilaco), was anodized in 3 L of a 0.5 wt% HF solution (Wako Chemicals) under stirring. The counter electrode was a Pt-sputtered stainless steel electrode with a size of around 10 × 10 cm. The voltage was provided by a custom-built direct-current (DC) power supply. The as-prepared TiO2 nanotubular layer was annealed at 500 °C under ambient air for 3 h to induce anatase crystallization.
Octadecyltrimethoxysilane (ODS, TCI, C21H46O3Si) molecules were deposited on the surface of a TiO2 nanotubular layer by a vapor reaction in a N2 atmosphere at 120 °C for 3 h [48]. The static water contact angles (CAs) were measured with a contact angle meter (Kyowa CA-X, Saitama, Japan). The evolution of water CAs under UV irradiation was performed with a 2 mW/cm2 mercury-xenon lamp.

3.2. Fabrication of a Pre-Designed Pattern and the Patterning of Oil-Based Ink

The pre-designed pattern on the TiO2 nanotubular layer for use as a UV-resistant photomask was fabricated by an ink-jet technique using a water-based ink [21,22]. The water-based ink was prepared by mixing a commercial dye (Tokyo Chemical Industry Co., Ltd., Tokyo, Japan, Direct Blue 86, 3 wt%) and pigment (BASF Japan Ltd., Tokyo, Japan, UVINUL3050, 2 wt%) into a mixed solvent of triethanolamine, diethylene glycol and deionized water (1:3:25, w/w/w). The water-based ink was effective in absorbing UV light, which functioned as a UV-resistant photomask. The TiO2 nanotubular layer with a pre-designed pattern was irradiated with a 7 mW/cm2 UV light (Philips-TUV75W) for 30 min. Then, the water-based ink patterns were removed by water washing. Finally, the oil-based ink (TOYO Ink) was then deposited on the surface of the TiO2 nanotubular layer by a hand roller.

3.3. Characterizations

The morphologies of the TiO2 nanotubular layer were studied using an FEI Quanta FEG 250 environmental scanning electron microscope (Hillsboro, OR, USA) (SEM) and a Bruker Dimension Icon atomic force microscope (Santa Barbara, CA, USA) (AFM). X-ray diffraction (XRD) patterns were measured on a Shimadzu XRD-6000 X-ray diffraction meter (Kyoto, Japan).

4. Conclusions

In summary, a large-area patterning of oil-based ink was achieved on a superhydrophobic TiO2 nanotubular layer based on a UV-induced photocatalytic wettability conversion. The pre-designed pattern of water-based UV-resistant ink on a superhydrophobic TiO2 nanotubular layer formed by an ink-jet technique was used as a photomask to selectively decompose the self-assembled molecular layers under UV irradiation. After removing the water-based ink patterns, the oil-based ink was selectively deposited on the superhydrophobic areas, which developed the corresponding pattern the same as the pre-designed pattern of water-based ink. This large-area patterning of an oil-based ink on a TiO2 nanotubular layer could be potentially applied for offset printing.

Author Contributions

Experiment, method, writing, J.J. and H.R.; Conceptualization, data analysis, writing, Z.L. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Aeronautical Science Foundation of China (2019ZD051012) and the Fundamental Research Funds for the Central Universities (YWF-20-BJ-J-416).

Acknowledgments

We thank Daibing Luo from the Analytical & Testing Center of Sichuan University for technical support.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Gau, H.; Herminghaus, S.; Lenz, P.; Lipowsky, R. Liquid morphologies on structured surfaces: From microchannels to microchips. Science 1999, 283, 46–49. [Google Scholar] [CrossRef] [Green Version]
  2. Burgess, I.B.; Mishchenko, L.; Hatton, B.D.; Kolle, M.; Lonĉar, M.; Aizenberg, J. Encoding complex wettability patterns in chemically functionalized 3D photonic crystals. J. Am. Chem. Soc. 2011, 133, 12430–12432. [Google Scholar] [CrossRef] [PubMed]
  3. Ito, Y. Surface micropatterning to regulate cell functions. Biomaterials 1999, 20, 2333–2342. [Google Scholar] [CrossRef]
  4. Gu, Z.; Fujishima, A.; Sato, O. Patterning of a colloidal crystal film on a modified hydrophilic and hydrophobic surface. Angew. Chem. Int. Ed. 2002, 41, 2068–2070. [Google Scholar]
  5. Jokinen, V.; Sainiemi, L.; Franssila, S. Complex droplets on chemically modified silicon nanograss. Adv. Mater. 2008, 20, 3453–3456. [Google Scholar] [CrossRef]
  6. Feng, S.; Wang, S.; Gao, L.; Li, G.; Hou, Y.; Zheng, Y. Controlled directional water-droplet spreading on a high-adhesion surface. Angew. Chem. Int. Ed. 2014, 53, 6163–6167. [Google Scholar] [CrossRef]
  7. Bai, H.; Wang, L.; Ju, J.; Sun, R.; Zheng, Y.; Jiang, L. Efficient water collection on integrative bioinspired surfaces with star-shaped wettability patterns. Adv. Mater. 2014, 26, 5025–5030. [Google Scholar] [CrossRef]
  8. Wu, Y.; Feng, J.; Gao, H.; Feng, X.; Jiang, L. Superwettability-based interfacial chemical reactions. Adv. Mater. 2019, 31, 1800718. [Google Scholar]
  9. Zhang, D.; Cheng, Z.; Kang, H.; Yu, J.; Liu, Y.; Jiang, L. A smart superwetting surface with responsivity in both surface chemistry and microstructure. Angew. Chem. Int. Ed. 2018, 57, 3701–3705. [Google Scholar] [CrossRef]
  10. Lim, H.S.; Han, J.T.; Kwak, D.; Jin, M.; Cho, K. Photoreversibly switchable superhydrophobic surface with erasable and rewritable pattern. J. Am. Chem. Soc. 2006, 128, 14458–14459. [Google Scholar] [CrossRef]
  11. Tian, D.; Chen, Q.; Nie, F.; Xu, J.; Song, Y.; Jiang, L. Patterned wettability transition by photoelectric cooperative and anisotropic wetting for liquid reprography. Adv. Mater. 2009, 21, 3744–3749. [Google Scholar] [CrossRef]
  12. Dai, H.; Dong, Z.; Jiang, L. Directional liquid dynamics of interfaces with superwettability. Sci. Adv. 2020, 6, eabb5528. [Google Scholar] [CrossRef]
  13. Tian, D.; Song, Y.; Jiang, L. Patterning of controllable surface wettability for printing techniques. Chem. Soc. Rev. 2013, 42, 5184–5209. [Google Scholar] [CrossRef] [PubMed]
  14. Si, Y.; Dong, Z.; Jiang, L. Bioinspired designs of superhydrophobic and superhydrophilic materials. ACS Cent. Sci. 2018, 4, 1102–1112. [Google Scholar] [CrossRef] [PubMed]
  15. Lai, Y.; Lin, C.; Wang, H.; Huang, J.; Zhuang, H.; Sun, L. Superhydrophilic-superhydrophobic micropattern on TiO2 nanotube films by photocatalytic lithography. Electrochem. Commun. 2008, 10, 387–391. [Google Scholar] [CrossRef]
  16. Zhang, X.; Jin, M.; Liu, Z.; Tryk, D.A.; Nishimoto, S.; Murakami, T.; Fujishima, A. Superhydrophobic TiO2 surfaces:  preparation, photocatalytic wettability conversion, and superhydrophobic−superhydrophilic patterning. J. Phys. Chem. C. 2007, 111, 14521–14529. [Google Scholar] [CrossRef]
  17. Zhang, X.; Kono, H.; Liu, Z.; Nishimoto, S.; Tryk, D.A.; Murakami, T.; Sakai, H.; Abe, M.; Fujishima, A. A transparent and photo-patternable superhydrophobic film. Chem. Commun. 2007, 46, 4949–4951. [Google Scholar] [CrossRef]
  18. Nakata, K.; Nishimoto, S.; Yuda, Y.; Ochiai, T.; Murakami, T.; Fujishima, A. Rewritable superhydrophilic-superhydrophobic patterns on a sintered titanium dioxide substrate. Langmuir 2010, 26, 11628–11630. [Google Scholar] [CrossRef]
  19. Nishimoto, S.; Sekine, H.; Zhang, X.; Liu, Z.; Nakata, K.; Murakami, T.; Koide, Y.; Fujishima, A. Assembly of self-assembled monolayer-coated Al2O3 on TiO2 thin films for the fabrication of renewable superhydrophobic-superhydrophilic structures. Langmuir 2009, 25, 7226–7228. [Google Scholar] [CrossRef] [PubMed]
  20. Nishimoto, S.; Kubo, A.; Zhang, X.; Liu, Z.; Taneichi, N.; Okui, T.; Murakami, T.; Komine, T.; Fujishima, A. Novel hydrophobic/hydrophilic patterning process by photocatalytic Ag nucleation on TiO2 thin film and electroless Cu deposition. Appl. Surf. Sci. 2008, 254, 5891–5894. [Google Scholar] [CrossRef]
  21. Nishimoto, S.; Kubo, A.; Nohara, K.; Zhang, X.; Taneichi, N.; Okui, T.; Liu, Z.; Nakata, K.; Sakai, H.; Murakami, T.; et al. TiO2-based superhydrophobic-superhydrophilic patterns: Fabrication via an ink-jet technique and application in offset printing. Appl. Surf. Sci. 2009, 255, 6221–6225. [Google Scholar] [CrossRef]
  22. Nakata, K.; Nishimoto, S.; Kubo, A.; Tryk, D.; Ochiai, T.; Murakami, T.; Fujishima, A. Fabrication and application of TiO2-based Superhydrophilic–superhydrophobic patterns on titanium substrates for offset printing. Chem. Asian J. 2009, 4, 984–988. [Google Scholar] [CrossRef] [PubMed]
  23. Nakata, K.; Fujishima, A. Titanium dioxide photocatalysis. J. Photochem. Photobiol. C 2000, 1, 1–21. [Google Scholar]
  24. Wang, R.; Hashimoto, K.; Fujishima, A.; Chikuni, M.; Kojima, E.; Kitamura, A.; Shimohigoshi, M.; Watanabe, T. Light-induced amphiphilic surfaces. Nature 1997, 388, 431–432. [Google Scholar] [CrossRef]
  25. Feng, X.; Zhai, J.; Jiang, L. The fabrication and switchable superhydrophobicity of TiO2 nanorod films. Angew. Chem. Int. Ed. 2005, 44, 5115–5118. [Google Scholar] [CrossRef] [PubMed]
  26. Liu, K.; Cao, M.; Fujishima, A.; Jiang, L. Bio-inspired titanium dioxide materials with special wettability and their applications. Chem. Rev. 2014, 114, 10044–10094. [Google Scholar] [CrossRef]
  27. Tadanaga, K.; Morinaga, J.; Matsuda, A.; Minami, T. Superhydrophobic-superhydrophilic micropatterning on flowerlike alumina coating film by the sol-gel method. Chem. Mater. 2000, 12, 590–592. [Google Scholar] [CrossRef]
  28. Zhang, X.; Jin, M.; Liu, Z.; Nishimoto, S.; Saito, H.; Murakami, T.; Fujishima, A. Preparation and photocatalytic wettability conversion of TiO2-based superhydrophobic surfaces. Langmuir 2006, 22, 9477–9479. [Google Scholar] [CrossRef]
  29. Järn, M.; Tåg, C.M.; Järnström, J.; Granqvist, B.; Rosenholm, J.B. Alternative models for determining the surface energy components in offset printing. J. Colloid Interface Sci. 2006, 301, 668–676. [Google Scholar] [CrossRef]
  30. Roy, P.; Berger, S.; Schmuki, P. TiO2 Nanotubes: Synthesis and applications. Angew. Chem. Int. Ed. 2011, 50, 2904–2939. [Google Scholar] [CrossRef]
  31. Lee, K.; Mazare, A.; Schmuki, P. One-dimensional titanium dioxide nanomaterials: Nanotubes. Chem. Rev. 2014, 114, 9385–9454. [Google Scholar] [CrossRef] [Green Version]
  32. Cai, Q.; Paulose, M.; Varghese, O.K.; Grimes, C.A. The effect of electrolyte composition on the fabrication of self-organized titanium oxide nanotube arrays by anodic oxidation. J. Mater. Res. 2005, 20, 230–236. [Google Scholar] [CrossRef]
  33. Ren, H.; Xiao, T.; Zhang, Q.; Liu, Z. Photosynthesis-inspired bifunctional energy-harvesting devices that convert light and salinity gradients into electricity. Chem. Commun. 2018, 54, 12310–12313. [Google Scholar] [CrossRef]
  34. Mao, X.; Xiao, T.; Zhang, Q.; Liu, Z. An electrochemical anodization strategy towards high-activity porous MoS2 electrodes for the hydrogen evolution reaction. RSC Adv. 2018, 8, 15030–15035. [Google Scholar] [CrossRef] [Green Version]
  35. Li, L.; Liu, Z.; Zhang, Q.; Meng, C.; Zhang, T.; Zhai, J. Underwater superoleophobic porous membrane based on hierarchical TiO2 nanotubes: Multifunctional integration of oil-water separation, flow-through photocatalysis and selfcleaning. J. Mater. Chem. A 2015, 3, 1279–1286. [Google Scholar] [CrossRef]
  36. Balaur, E.; Macak, J.M.; Tsuchiya, H.; Schmuki, P. Wetting behaviour of layers of TiO2 nanotubes with different diameters. J. Mater. Chem. 2005, 15, 4488–4491. [Google Scholar] [CrossRef]
  37. Balaur, E.; Macak, J.M.; Taveira, L.; Schmuki, P. Tailoring the wettability of TiO2 nanotube layers. Electrochem. Commun. 2005, 7, 1066–1070. [Google Scholar] [CrossRef]
  38. Lai, Y.; Gao, X.; Zhuang, H.; Huang, J.; Lin, C.; Jiang, L. Designing superhydrophobic porous nanostructures with tunable water adhesion. Adv. Mater. 2009, 21, 3799–38032. [Google Scholar] [CrossRef] [Green Version]
  39. Hu, Z.; Zhang, X.; Liu, Z.; Huo, K.; Chu, P.K.; Zhai, J.; Jiang, L. Regulating water adhesion on superhydrophobic TiO2 nanotube arrays. Adv. Funct. Mater. 2014, 24, 6381–6388. [Google Scholar] [CrossRef]
  40. Liu, Z.; Zhang, X.; Nishimoto, S.; Murakami, T.; Fujishima, A. Efficient photocatalytic degradation of gaseous acetaldehyde by highly ordered TiO2 nanotube arrays. Environ. Sci. Technol. 2008, 42, 8547–8551. [Google Scholar] [CrossRef]
  41. Feng, X.; Jiang, L. Design and creation of superwetting/antiwetting surfaces. Adv. Mater. 2006, 18, 3063–3078. [Google Scholar] [CrossRef]
  42. Lafuma, A.; Quéré, D. Superhydrophobic states. Nat. Mater. 2003, 2, 457–460. [Google Scholar] [CrossRef] [PubMed]
  43. Cassie, A.B.D.; Baxter, S. Wettability of porous surfaces. Trans. Faraday Soc. 1944, 40, 546–561. [Google Scholar] [CrossRef]
  44. Sun, T.; Feng, L.; Gao, X.; Jiang, L. Bioinspired surfaces with special wettability. Acc. Chem. Res. 2005, 38, 644–652. [Google Scholar] [CrossRef]
  45. Tatsuma, T.; Tachibana, S.; Miwa, T.; Tryk, D.A.; Fujishima, A. Remote bleaching of methylene blue by UV-irradiated TiO2 in the gas phase. J. Phys. Chem. B 1999, 103, 8033–8035. [Google Scholar] [CrossRef]
  46. Tatsuma, T.; Tachibana, S.; Fujishima, A. Remote oxidation of organic compounds by UV-irradiated TiO2 via the gas phase. J. Phys. Chem. B 2001, 105, 6987–6992. [Google Scholar] [CrossRef]
  47. Tatsuma, T.; Kubo, W.; Fujishima, A. Patterning of solid surfaces by photocatalytic lithography based on the remote oxidation effect of TiO2. Langmuir 2002, 18, 9632–9634. [Google Scholar] [CrossRef]
  48. Liu, Z.; Zhang, X.; Murakami, T.; Fujishima, A. Sol–gel SiO2/TiO2 bilayer films with self-cleaning and antireflection properties. Sol. Energy Mater. Sol. C 2008, 92, 1434–1438. [Google Scholar] [CrossRef]
Catalysts 10 01203 sch001 550
Scheme 1. The schematic process for the patterning of oil-based ink on a TiO2 nanotubular layer. Firstly, a TiO2 nanotubular layer was formed on Ti metal by anodization (Step 1). A superhydrophobic surface was obtained by modified octadecyltrimethoxysilane (ODS) self-assembled molecular layers (Step 2). Then, a pre-designed pattern of water-based ink was formed on the superhydrophobic surface by an ink-jet technique (Step 3). After UV irradiation (Step 4) and a subsequent water washing (Step 5), a wettability difference was formed on the surface. Finally, an oil-based ink was deposited selectively on the superhydrophobic area (Step 6), which developed a corresponding pattern the same as the pre-designed pattern of water-based ink. The diagram was not drawn to scale.
Scheme 1. The schematic process for the patterning of oil-based ink on a TiO2 nanotubular layer. Firstly, a TiO2 nanotubular layer was formed on Ti metal by anodization (Step 1). A superhydrophobic surface was obtained by modified octadecyltrimethoxysilane (ODS) self-assembled molecular layers (Step 2). Then, a pre-designed pattern of water-based ink was formed on the superhydrophobic surface by an ink-jet technique (Step 3). After UV irradiation (Step 4) and a subsequent water washing (Step 5), a wettability difference was formed on the surface. Finally, an oil-based ink was deposited selectively on the superhydrophobic area (Step 6), which developed a corresponding pattern the same as the pre-designed pattern of water-based ink. The diagram was not drawn to scale.
Catalysts 10 01203 sch001
Catalysts 10 01203 g001 550
Figure 1. (A) A photograph of a large-area TiO2 nanotubular layer, which demonstrated a uniform surface visible color. (B,C) Top-viewed (B) and cross-sectional (C) SEM images of the TiO2 nanotubular layer. (D) The XRD investigation identified the anatase phase of the TiO2 nanotubular layer.
Figure 1. (A) A photograph of a large-area TiO2 nanotubular layer, which demonstrated a uniform surface visible color. (B,C) Top-viewed (B) and cross-sectional (C) SEM images of the TiO2 nanotubular layer. (D) The XRD investigation identified the anatase phase of the TiO2 nanotubular layer.
Catalysts 10 01203 g001
Catalysts 10 01203 g002 550
Figure 2. (A) The atomic force microscope (AFM) morphology of a TiO2 nanotubular layer. (B) The static water contact angle (CA) of an as-prepared TiO2 nanotubular layer, which demonstrated a superhydrophilicity. (C) After being modified with ODS self-assembled molecular layers (SAMs), the TiO2 nanotubular layer showed a superhydrophobic state. (D) The static water CAs of six samples containing ODS-modified large-area TiO2 nanotubular layers were prepared in one HF electrolyte successively.
Figure 2. (A) The atomic force microscope (AFM) morphology of a TiO2 nanotubular layer. (B) The static water contact angle (CA) of an as-prepared TiO2 nanotubular layer, which demonstrated a superhydrophilicity. (C) After being modified with ODS self-assembled molecular layers (SAMs), the TiO2 nanotubular layer showed a superhydrophobic state. (D) The static water CAs of six samples containing ODS-modified large-area TiO2 nanotubular layers were prepared in one HF electrolyte successively.
Catalysts 10 01203 g002
Catalysts 10 01203 g003 550
Figure 3. The evolution of the static water CAs of the ODS SAMs-modified TiO2 nanotubular layer under UV irradiation. Inset: the corresponding images for the measurement of water CA. After UV irradiation, the superhydrophobic TiO2 nanotubular layer converted to be superhydrophilic.
Figure 3. The evolution of the static water CAs of the ODS SAMs-modified TiO2 nanotubular layer under UV irradiation. Inset: the corresponding images for the measurement of water CA. After UV irradiation, the superhydrophobic TiO2 nanotubular layer converted to be superhydrophilic.
Catalysts 10 01203 g003
Catalysts 10 01203 g004 550
Figure 4. (A) A pre-designed pattern of water-based ink was formed on the surface of a superhydrophobic TiO2 nanotubular layer by an ink-jet technique, which functioned as a UV-resistant photomask. (B,C) The morphologies of the line with (B) and without (C) ink imaged with an optical microscope. A clear boundary between the TiO2 nanotubular substrate and ink was observed. (D) The patterning of the oil-based ink after the TiO2 nanotubular layer with a pre-designed pattern of water-based ink was illuminated by UV light and subsequently washed by water.
Figure 4. (A) A pre-designed pattern of water-based ink was formed on the surface of a superhydrophobic TiO2 nanotubular layer by an ink-jet technique, which functioned as a UV-resistant photomask. (B,C) The morphologies of the line with (B) and without (C) ink imaged with an optical microscope. A clear boundary between the TiO2 nanotubular substrate and ink was observed. (D) The patterning of the oil-based ink after the TiO2 nanotubular layer with a pre-designed pattern of water-based ink was illuminated by UV light and subsequently washed by water.
Catalysts 10 01203 g004
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Jin, J.; Ren, H.; Liu, Z. Large-Area Patterning of Oil-Based Inks on Superhydrophobic TiO2 Nanotubular Layers by Photocatalytic Wettability Conversion. Catalysts 2020, 10, 1203. https://doi.org/10.3390/catal10101203

AMA Style

Jin J, Ren H, Liu Z. Large-Area Patterning of Oil-Based Inks on Superhydrophobic TiO2 Nanotubular Layers by Photocatalytic Wettability Conversion. Catalysts. 2020; 10(10):1203. https://doi.org/10.3390/catal10101203

Chicago/Turabian Style

Jin, Jiao, Huihui Ren, and Zhaoyue Liu. 2020. "Large-Area Patterning of Oil-Based Inks on Superhydrophobic TiO2 Nanotubular Layers by Photocatalytic Wettability Conversion" Catalysts 10, no. 10: 1203. https://doi.org/10.3390/catal10101203

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

Article Metrics

Back to TopTop