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A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Electronic Materials".

Deadline for manuscript submissions: closed (31 December 2020) | Viewed by 32237

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Prof. Dr. Ewa Schab-Balcerzak

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1. Institute of Chemistry, University of Silesia, 40-007 Katowice, Poland
2. Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Skłodowska Str., 41-819 Zabrze, Poland
Interests: azopolymers; organic materials for optoelectronics; dyes sensitized (DSSC); perovskite (PSC) and bulk heterojunction (BHJ) solar cells
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Dear Colleagues,

Low and high molecular weight compounds with spatially extended p-p or p-n-p bonding systems have great potential for applications in modern fields of science and technology, such as organic optoelectronics and organic photonics, which have seen intense development in recent years. Although remarkable progress has been made and some technologies have grown from a research laboratory concept to commercial applications there is still room for improvement of device parameters including efficiency, lifetime, and cost-effectiveness. A key issue in the development of organic optoelectronics and photonics is organic material and device architecture. The aim of this Special Issue, entitled "Advances in Materials for Organic Optoelectronics and Photonics” is to address current challenges associated with design, synthesis, and characterization of new functional materials aiming at their utilization in optoelectronic and photonic devices.

I would like to cordially invite you to share your outstanding achievements and submit a paper to this Special Issue.

Prof. Dr. Ewa Schab-Balcerzak
Guest Editor

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Keywords

organic semiconductors
hole-transporting compounds
low and high molecular weight compounds
azopolymers
photoinduced anisotropy
organic light emitting diodes
photovoltaic cells
organic field-effect transistors

Published Papers (12 papers)

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Research

17 pages, 5881 KiB

Open AccessArticle

Impact of TiO₂ Nanostructures on Dye-Sensitized Solar Cells Performance

by Paweł Gnida, Paweł Jarka, Pavel Chulkin, Aleksandra Drygała, Marcin Libera, Tomasz Tański and Ewa Schab-Balcerzak

Materials 2021, 14(7), 1633; https://doi.org/10.3390/ma14071633 - 26 Mar 2021

Cited by 28 | Viewed by 2989

Abstract

The effect of TiO₂ nanostructures such as nanoparticles, nanowires, nanotubes on photoanode properties, and dye-sensitized solar cells photovoltaic parameters were studied. The series of dye-sensitized solar cells based on two dyes, that is, commercially N719 and synthesized 3,7′-bis(2-cyano-1-acrylic acid)-10-ethyl-phenothiazine were tested. Additionally, the devices containing a mixture of this sensitizer and chenodeoxycholic acid as co-adsorbent were fabricated. The amount of adsorbed dye molecules to TiO₂ was evaluated. The prepared photoanodes with different TiO₂ nanostructures were investigated using UV-Vis spectroscopy, optical, atomic force, and scanning electron microscopes. Photovoltaic response of constructed devices was examined based on current-voltage characteristics and electrochemical impedance spectroscopy measurements. It was found that the highest UV-Vis absorption exhibited the photoanode with nanotubes addition. This indicates the highest number of sensitizer molecules anchored to the titanium dioxide photoanode, which was subsequently confirmed by dye-loading tests. The highest power conversion efficiency was (6.97%) for solar cell containing nanotubes and a mixture of the dyes with a co-adsorbent. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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15 pages, 7131 KiB

Open AccessArticle

Impact of Acidity Profile on Nascent Polyaniline in the Modified Rapid Mixing Process—Material Electrical Conductivity and Morphological Study

by Sylwia Golba, Magdalena Popczyk, Seweryn Miga, Justyna Jurek-Suliga, Maciej Zubko, Julian Kubisztal and Katarzyna Balin

Materials 2020, 13(22), 5108; https://doi.org/10.3390/ma13225108 - 12 Nov 2020

Cited by 7 | Viewed by 1545

Abstract

Polyaniline (PANI) was synthesized chemically with the modified rapid mixing protocol in the presence of sulfuric acid of various concentrations. A two-step synthetic procedure was utilized maintaining low-temperature conditions. Application of the modified rapid mixing protocol allowed obtaining a material with local ordering. A higher concentration of acid allowed obtaining a higher yield of the reaction. Structural characterization performed with Fourier-transform infrared (FTIR) analysis showed the vibration bands characteristic of the formation of the emeraldine salt in both products. Ultraviolet–visible light (UV–Vis) spectroscopy was used for the polaronic band and the p–p* band determination. The absorption result served to estimate the average oxidation level of PANI by comparison of the ratio of the absorbance of the polaronic band to that of the π–π* transition. The absorbance ratio index was higher for PANI synthesized in a more acidic solution, which showed a higher doping level for this polymer. For final powder products, particle size distributions were also estimated, proving that PANI (5.0 M) is characterized by a larger number of small particles; however, these particles can more easily agglomerate and form larger structures. The X-ray diffraction (XRD) patterns revealed an equilibrium between the amorphous and semicrystalline phase in the doped PANI. A higher electrical conductivity value was measured for polymer synthesized in a higher acid concentration. The time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis showed that the molecular composition of the polymers was the same; hence, the difference in properties was a result of local ordering. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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12 pages, 2350 KiB

Open AccessArticle

Bottom Contact Metal Oxide Interface Modification Improving the Efficiency of Organic Light Emitting Diodes

by Sergey M. Pozov, Apostolos Ioakeimidis, Ioannis T. Papadas, Chen Sun, Alexandra Z. Chrusou, Donal D. C. Bradley and Stelios A. Choulis

Materials 2020, 13(22), 5082; https://doi.org/10.3390/ma13225082 - 11 Nov 2020

Cited by 5 | Viewed by 2372

Abstract

The performance of solution-processed organic light emitting diodes (OLEDs) is often limited by non-uniform contacts. In this work, we introduce Ni-containing solution-processed metal oxide (MO) interfacial layers inserted between indium tin oxide (ITO) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) to improve the bottom electrode contact for OLEDs using the poly(p-phenylene vinylene) (PPV) derivative Super-Yellow (SY) as an emission layer. For ITO/Ni-containing MO/PEDOT:PSS bottom electrode structures we show enhanced wetting properties that result in an improved OLED device efficiency. Best performance is achieved using a Cu-Li co-doped spinel nickel cobaltite [(Cu-Li):NiCo₂O₄], for which the current efficiency and luminous efficacy of SY OLEDs increased, respectively, by 12% and 11% from the values obtained for standard devices without a Ni-containing MO interface modification between ITO and PEDOT:PSS. The enhanced performance was attributed to the improved morphology of PEDOT:PSS, which consequently increased the hole injection capability of the optimized ITO/(Cu-Li):NiCo₂O₄/PEDOT:PSS electrode. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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20 pages, 4831 KiB

Open AccessArticle

An Insight into Ionic Conductivity of Polyaniline Thin Films

by Pavel Chulkin and Mieczysław Łapkowski

Materials 2020, 13(12), 2877; https://doi.org/10.3390/ma13122877 - 26 Jun 2020

Cited by 16 | Viewed by 2954

Abstract

The work addresses an issue of the conductivity phenomenon in conductive polymer thin films. Polyaniline was chosen as a broadly used and thoroughly investigated conductive polymer in order to test and show capabilities of the developed original approach based on impedance spectra analysis. A number of films of different thickness were deposited onto a Pt electrode surface and consequently investigated in aqueous solution containing perchloric acid as an electrolyte. The processes that occur in polyaniline film were studied by cyclic voltammetry, electrochemical quartz crystal microgravimetry (EQCM) and electrochemical impedance spectroscopy (EIS). The role of incorporated ions as charge carriers was investigated with respect to the control of the conductivity properties of the film. Along with detailed polyaniline behavior study, the work makes up a fundamental scientific impact on theoretical electrochemistry and electroanalytical techniques. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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16 pages, 4386 KiB

Open AccessArticle

Preparation and Characterization of Novel Polymer-Based Gel Electrolyte for Dye-Sensitized Solar Cells Based on poly(vinylidene fluoride-co-hexafluoropropylene) and poly(acrylonitrile-co-butadiene) or poly(dimethylsiloxane) bis(3-aminopropyl) Copolymers

by Krzysztof Artur Bogdanowicz, Dariusz Augustowski, Justyna Dziedzic, Paweł Kwaśnicki, Wacław Malej and Agnieszka Iwan

Materials 2020, 13(12), 2721; https://doi.org/10.3390/ma13122721 - 15 Jun 2020

Cited by 14 | Viewed by 2505

Abstract

Polymer gel electrolytes based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and poly(acrylonitrile-co-butadiene) (PAB) or poly(dimethylsiloxane) bis(3-aminopropyl)-terminated (PDES-bAP) copolymers were prepared and investigated in dye-sensitized solar cells (DSSCs). Selected optical and electrochemical properties of all compositions with various ratio from 9:1 to 6:4 were investigated towards DSSC applications. The highest value of power conversion efficiency equal to 5.07% was found for DSSCs containing a PVDF-HPF:PAB (9:1) gel electrolyte. Compositions of electrolytes were additionally tested by electrochemical impedance spectroscopy. The influence of the ratio and type of polymers used as an additive to PVDF-HPF on absorption wavelengths, energy gap, and Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) levels were investigated. Individual components of DSSCs, such as the TiO₂ layer and platinum nanoparticles, were imaged by scanning electron microscope. Finally, a DSSC module with six electrically separated solar cells with a 7 × 80 mm² active area was constructed based on gel electrolytes and tested. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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18 pages, 5455 KiB

Open AccessArticle

Energy Transfer Study on Tb³⁺/Eu³⁺ Co-Activated Sol-Gel Glass-Ceramic Materials Containing MF₃ (M = Y, La) Nanocrystals for NUV Optoelectronic Devices

by Natalia Pawlik, Barbara Szpikowska-Sroka and Wojciech A. Pisarski

Materials 2020, 13(11), 2522; https://doi.org/10.3390/ma13112522 - 01 Jun 2020

Cited by 12 | Viewed by 2103

Abstract

In the present work, the Tb³⁺/Eu³⁺ co-activated sol-gel glass-ceramic materials (GCs) containing MF₃ (M = Y, La) nanocrystals were fabricated during controlled heat-treatment of silicate xerogels at 350 °C. The studies of Tb³⁺ → Eu³⁺ energy transfer process (ET) were performed by excitation and emission spectra along with luminescence decay analysis. The co-activated xerogels and GCs exhibit multicolor emission originated from 4fⁿ–4fⁿ optical transitions of Tb³⁺ (⁵D₄ → ⁷F_J, J = 6–3) as well as Eu³⁺ ions (⁵D₀ → ⁷F_J, J = 0–4). Based on recorded decay curves, it was found that there is a significant prolongation in luminescence lifetimes of the ⁵D₄ (Tb³⁺) and the ⁵D₀ (Eu³⁺) levels after the controlled heat-treatment of xerogels. Moreover, for both types of prepared GCs, an increase in ET efficiency was also observed (from η_ET ≈ 16% for xerogels up to η_ET = 37.3% for SiO₂-YF₃ GCs and η_ET = 60.8% for SiO₂-LaF₃ GCs). The changes in photoluminescence behavior of rare-earth (RE³⁺) dopants clearly evidenced their partial segregation inside low-phonon energy fluoride environment. The obtained results suggest that prepared SiO₂-MF₃:Tb³⁺, Eu³⁺ GC materials could be considered for use as optical elements in RGB-lighting optoelectronic devices operating under near-ultraviolet (NUV) excitation. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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17 pages, 4270 KiB

Open AccessArticle

Thermocapillary Marangoni Flows in Azopolymers

by Andrzej Miniewicz, Anna Sobolewska, Wojciech Piotrowski, Pawel Karpinski, Stanislaw Bartkiewicz and Ewa Schab-Balcerzak

Materials 2020, 13(11), 2464; https://doi.org/10.3390/ma13112464 - 28 May 2020

Cited by 10 | Viewed by 2806

Abstract

It is well known that light-induced multiple trans-cis-trans photoisomerizations of azobenzene derivatives attached to various matrices (polymeric, liquid crystalline polymers) result in polymer mass movement leading to generation of surface reliefs. The reliefs can be produced at small as well as at large light intensities. When linearly polarized light is used in the process, directional photo-induced molecular orientation of the azo molecules occurs, which leads to the generation of optical anisotropy in the system, providing that thermal effects are negligible. On the other hand, large reliefs are observed at relatively strong laser intensities when the optofluidization process is particularly effective. In this article, we describe the competitive thermocapillary Marangoni effect of polymer mass motion. We experimentally prove that the Marangoni effect occurs simultaneously with the optofluidization process. It destroys the orientation of the azopolymer molecules and results in cancelation of the photo-induced birefringence. Our experimental observations of polymer surface topography with atomic force microscopy are supported by suitable modelings. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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17 pages, 6662 KiB

Open AccessArticle

Selected Electrochemical Properties of 4,4’-((1E,1’E)-((1,2,4-Thiadiazole-3,5-diyl)bis(azaneylylidene))bis(methaneylylidene))bis(N,N-di-p-tolylaniline) towards Perovskite Solar Cells with 14.4% Efficiency

by Krzysztof Artur Bogdanowicz, Beata Jewłoszewicz, Agnieszka Iwan, Karolina Dysz, Wojciech Przybyl, Adam Januszko, Monika Marzec, Kacper Cichy, Konrad Świerczek, Ladislav Kavan, Markéta Zukalová, Vojtech Nadazdy, Riyas Subair, Eva Majkova, Matej Micusik, Maria Omastova, Mehmet Derya Özeren, Katalin Kamarás, Do Yeon Heo and Soo Young Kim

Materials 2020, 13(11), 2440; https://doi.org/10.3390/ma13112440 - 27 May 2020

Cited by 19 | Viewed by 3205

Abstract

Planar perovskite solar cells were fabricated on F-doped SnO₂ (FTO) coated glass substrates, with 4,4’-((1E,1’E)-((1,2,4-thiadiazole-3,5-diyl)bis(azaneylylidene))bis(methaneylylidene))bis(N,N-di-p-tolylaniline) (bTAThDaz) as hole transport material. This imine was synthesized in one step reaction, starting from commercially available and relatively inexpensive reagents. Electrochemical, optical, electrical, thermal and structural studies including thermal images and current-voltage measurements of the full solar cell devices characterize the imine in details. HOMO-LUMO of bTAThDaz were investigated by cyclic voltammetry (CV) and energy-resolved electrochemical impedance spectroscopy (ER-EIS) and were found at −5.19 eV and −2.52 eV (CV) and at −5.5 eV and −2.3 eV (ER-EIS). The imine exhibited 5% weight loss at 156 °C. The electrical behavior and photovoltaic performance of the perovskite solar cell was examined for FTO/TiO₂/perovskite/bTAThDaz/Ag device architecture. Constructed devices exhibited good time and air stability together with quite small effect of hysteresis. The observed solar conversion efficiency was 14.4%. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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17 pages, 12889 KiB

Open AccessArticle

Investigations of New Phenothiazine-Based Compounds for Dye-Sensitized Solar Cells with Theoretical Insight

by Aneta Slodek, Dawid Zych, Grażyna Szafraniec-Gorol, Paweł Gnida, Marharyta Vasylieva and Ewa Schab-Balcerzak

Materials 2020, 13(10), 2292; https://doi.org/10.3390/ma13102292 - 15 May 2020

Cited by 40 | Viewed by 2898

Abstract

New D-π-D-π-A low-molecular-weight compounds, based on a phenothiazine scaffold linked via an acetylene unit with various donor moiety and cyanoacrylic acid anchoring groups, respectively, were successfully synthesized. The prepared phenothiazine dyes were entirely characterized using nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. The compounds were designed to study the relationship between end-capping donor groups’ structure on their optoelectronic and thermal properties as well as the dye-sensitized solar cells’ performance. The effect of π-conjugation enlargement by incorporation of different heterocyclic substituents possessing various electron–donor affinities was systematically experimentally and theoretically examined. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were implemented to determine the electronic properties of the novel molecules. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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16 pages, 2952 KiB

Open AccessFeature PaperArticle

Azobenzene Functionalized “T-Type” Poly(Amide Imide)s vs. Guest-Host Systems—A Comparative Study of Structure-Property Relations

by Karolina Bujak, Anna Kozanecka-Szmigiel, Ewa Schab-Balcerzak and Jolanta Konieczkowska

Materials 2020, 13(8), 1912; https://doi.org/10.3390/ma13081912 - 18 Apr 2020

Cited by 5 | Viewed by 2054

Abstract

This paper describes the synthesis and characterization of new “T-type” azo poly(amide imide)s as well as guest-host systems based on the “T-type” matrices. The matrices possessed pyridine rings in a main-chain and azobenzene moieties located either between the amide or imide groups. The non-covalent polymers contained the molecularly dispersed 4-phenylazophenol or 4-[(4-methyl phenyl)diazinyl]phenol chromophores that are capable of forming intermolecular hydrogen bonds with the pyridine rings. The FTIR spectroscopy and the measurements of the thermal, optical and photoinduced optical birefringence were employed for the determination of the influence of H-bonds and the specific elements of polymer architecture on physicochemical properties. Moreover, the obtained results were compared to those described in our previous works to formulate structure-property relations that may be considered general for the class of “T-type” azo poly(amide imide)s. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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15 pages, 1880 KiB

Open AccessArticle

The Quantum Efficiency Roll-Off Effect in Near-Infrared Organic Electroluminescent Devices with Iridium Complexes Emitters

by Wojciech Mróz, Sagar Kesarkar, Alberto Bossi, Daniel Pelczarski, Piotr Grygiel and Waldemar Stampor

Materials 2020, 13(8), 1855; https://doi.org/10.3390/ma13081855 - 15 Apr 2020

Cited by 4 | Viewed by 2362

Abstract

The electroluminescence quantum efficiency roll-off in iridium(III)-based complexes, namely Ir(iqbt)₂(dpm) and Ir(iqbt)₃ (iqbt = 1 (benzo[b]thiophen-2-yl)-isoquinolinate, dpm = 2,2,6,6-tetramethyl-3,5-heptanedionate) utilized as near-infrared emitters in organic light emitting diodes with remarkable external quantum efficiencies, up to circa 3%, 1.5% and 1%, are measured and analyzed. With a 5–6 weight% of emitters embedded in a host matrix, the double-layer solution-processed structure as well as analogous three-layer one extended by a hole-conducting film are investigated. The triplet-polaron, the Onsager electron-hole pair dissociation and the triplet-triplet annihilation approaches were used to reproduce the experimental data. The mutual annihilation of triplets in iridium emitters was identified as prevailingly controlling the moderate roll-off, with the interaction between those of iridium emitters and host matrixes found as being less probable. Following the fitting procedure, the relevant rate constant was estimated to be

(0.5 - 12) \times 10^{- 12}

cm³/s, values considered to be rather too high for disordered organic systems, which was assigned to the simplicity of the applied model. A coexistence of some other mechanisms is therefore inferred, ones, however, with a less significant contribution to the overall emission quenching. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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26 pages, 6683 KiB

Open AccessArticle

UV–Vis Absorption Properties of New Aromatic Imines and Their Compositions with Poly({4,8-bis[(2-Ethylhexyl)oxy]Benzo[1,2-b:4,5-b′]Dithiophene-2,6-diyl}{3-Fluoro-2-[(2-Ethylhexyl)Carbonyl]Thieno[3,4-b]Thiophenediyl})

by Agnieszka Gonciarz, Robert Pich, Krzysztof Artur Bogdanowicz, Beata Jewloszewicz, Wojciech Przybył, Karolina Dysz, Agnieszka Dylong, Anna Kwak, Andrzej Kaim, Agnieszka Iwan, Jaroslaw Rusin and Adam Januszko

Materials 2019, 12(24), 4191; https://doi.org/10.3390/ma12244191 - 13 Dec 2019

Cited by 13 | Viewed by 3571

Abstract

In this paper, four new aromatic imines containing at least one thiazole-based heterocycle were analyzed in detail by UV–Vis spectroscopy, taking into consideration their chemical structures and interactions with PTB7, a known polymeric electron donor widely used in bulk heterojunction organic solar cells. It is demonstrated that the absorption spectra of the investigated active compositions can be modified not only by changing the chemical structure of imine, but also via formulations with PTB7. For all investigated imines and PTB7:imine compositions, calibration curves were obtained in order to find the optimum concentration in the composition with PTB7 for expansion and optimization of absorption spectra. All imines and PTB7:imine compositions were investigated in 1,2-dichlorobenzene by UV–Vis spectroscopy in various concentrations, monitoring the changes in the π–π* and n–π* transitions. With increasing imine concentrations, we did not observe changes in absorption maxima, while with increasing imine concentrations, a hypochromic effect was observed. Finally, we could conclude that all investigated compositions exhibited wide absorptions of up to 800 nm and isosbestic points in the range of 440–540 nm, confirming changes in the macromolecular organization of the tested compounds. The theoretical calculations of their vibration spectra (FTIR) and LUMO–HOMO levels by Density Functional Theory (DFT) methods are also provided. Finally, IR thermal images were measured for organic devices based on imines and the imine:PTB7 composite. Full article

(This article belongs to the Special Issue Advances in Materials for Organic Optoelectronics and Photonics)

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