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Polymeric mixed ionic–electronic conductors hold great potential for advancing high‐performance organic electronics due to their exceptional electrical conductivity achieved through ion–electron coupling. However, the widespread adoption of these conductors faces obstacles due to their reliance on environmentally harmful solvents during processing and the potential performance degradation under various conditions. In this study, a practical solution to these challenges is proposed by incorporating monomers with ionic liquid‐behaving pendant groups into conjugated polymers. The copolymerization of these charged monomers not only improves solubility in environmentally friendly solvents but also imparts long‐term stability against humidity, high temperatures, and mechanical deformation. The immobilized ion species foster highly selective interactions of these polymers with nitrogen dioxide, paving the way for the development of stretchable sensing devices capable of functioning at exceptionally high temperatures. [ABSTRACT FROM AUTHOR]

Chirality‐induced spin selectivity observed in chiral 2D organic–inorganic hybrid perovskite holds promise to achieve spin‐dependent electrochemistry. However, conventional chiral 2D perovskites suffer from low conductivity and hygroscopicity, limiting electrochemical performance and operational stability. Here, a cutting‐edge material design is introduced to develop a stable and efficient chiral perovskite‐based spin polarizer by employing fluorinated chiral cation. The fluorination approach effectively promotes the charge carrier transport along the out‐of‐plane direction by mitigating the dielectric confinement effect within the multi‐quantum well‐structured 2D perovskite. Integrating the fluorinated cation incorporated spin polarizer with BiVO4 photoanode considerably boosts the photocurrent density while reducing overpotential through a spin‐dependent oxygen evolution reaction. Furthermore, the hydrophobic nature of fluorine in spin polarizer endows operational stability to the photoanode, extending the durability by 280% as compared to the device with non‐fluorinated spin polarizer. [ABSTRACT FROM AUTHOR]

Chiral perovskites have emerged as promising next‐generation materials for polarization detection due to their excellent circularly polarized light (CPL) detection capabilities. However, they suffer from a low chiroptical response when fabricated as a polycrystalline thin film, limiting their potential range of applications. Herein, it is demonstrated that antisolvent dripping during the spin‐coating process can effectively improve the chiroptical properties of polycrystalline chiral perovskite thin films. Systematic analysis with different antisolvents reveals that the highly polar antisolvent chloroform interacts with dimethyl sulfoxide molecules via hydrogen bonding. This strong hydrogen bonding suppresses the formation of intermediate and secondary phases and accelerates the crystallization of chiral 1D perovskites, thus reducing the density of the iodine vacancies inside the perovskite thin films. The lower density of iodine vacancies also intensifies the asymmetric tilting inorganic distortion of PbI6 octahedrons, enhancing the chiroptical response of the fabricated chiral perovskite material. Photodetectors based on the chloroform‐treated chiral perovskite films achieve a remarkably high distinguishability of 0.31, outperforming previously reported photodetectors based on the chiral perovskites. The fabricated photodetectors also exhibit outstanding responsivity and detectivity with enhanced operational stability. [ABSTRACT FROM AUTHOR]

Although ionic hydrogels have been developed recently for innovative wearable electronics, they necessitate high humidity to diffuse ions in water and fast self‐healing, which negatively impacts their performance and stability in ambient conditions (e.g., dry environments). In this study, a series of p‐ and n‐type polymeric ionic gels (PIGs) with different ratios of ionic side chains are synthesized to allow only single‐type ions to pass through them. The results demonstrate that the repeatedly stretchable PIGs are transparent, thermally robust up to 125°C, and self‐healing. Among the series of PIGs, p‐ and n‐type PIGs with 75% ion moieties (P75 and N75) exhibit the optimum ionic conductivity (σi) (4.1 × 10−4 and 2.7 × 10−4 S cm−1) and ionic Seebeck coefficients (Si) (5.84, and ‐4.18 mV K−1) under ambient conditions (25°C and relative humidity (RH) of 30%), resulting in ZTi values of 1.87 × 10−3 and 1.18 × 10−3. Moreover, the σi and Si of PIGs are almost consistent under extremely low RH 10%. Accordingly, P(([EMIM+][SPA])0.75‐r‐MA0.25) (P75) and P(([APTA][TFSI−])0.75‐r‐MA0.25) (N75) are used to achieve stretchable ionic thermoelectrics (iTEs) with stable operability under ambient conditions (RH of 30%), satisfying all of the requirements. The iTEs with five pairs of p/n couples exhibit a thermovoltage of up to ∼0.8 V. [ABSTRACT FROM AUTHOR]

Recently, lead halide perovskites have attracted significant attention as promising absorber materials for photoelectrochemical (PEC) solar water splitting. However, charge‐accumulation‐induced ion migration at the interface causes perovskite degradation and efficiency loss. To suppress the charge accumulation and improve the PEC performance of the perovskite photoanode, a simple interface engineering is proposed by decorating the SnO2/perovskite interface with a mixture of polyethylenimine ethoxylated (PEIE) and chlorobenzenesulfonic acid (CBSA). The mixed CBSA+PEIE treatment effectively passivates the oxygen vacancies in SnO2 and adjusts the band alignment between SnO2 and the perovskite. The synergistic effects of the mixture treatment facilitate an effective carrier extraction at the SnO2/perovskite interface, enhance the PEC performance, and improve the stability of the device. The perovskite photoanode exhibits an impressive applied bias photon‐to‐current efficiency of 12.9% with an outstanding durability for 225 h. Furthermore, an unbiased solar water splitting is achieved using all the perovskite photoelectrodes, resulting in a remarkable unassisted solar‐to‐hydrogen efficiency of 10.9% and a continuous 22 h stable operation. [ABSTRACT FROM AUTHOR]

Mechanically compliant conductors are of utmost importance for the emerging fields of soft electronics and robotics. However, the development of intrinsically deformable organic conductors remains a challenge due to the trade‐off between mechanical performance and charge mobility. In this study, we report a solution to this issue based on size‐selective ionic crosslinking. This rationally designed crosslinking mediated by length‐regulated oligo(ethylene glycol) pendant groups and metal ions simultaneously improved the softness and toughness and ensured excellent mixed ionic–electronic conductivity in poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate composite materials. Moreover, the added ions remarkably promoted accumulation of charge carriers in response to temperature gradient, thus offering a viable approach to stretchable thermoelectric generators with enhanced stability against humidity. [ABSTRACT FROM AUTHOR]

For efficient colloidal quantum dot (CQD) solar cells (CQD‐SCs), thiol‐passivated p‐type CQDs are generally used as a hole‐transporting material (HTM); however, there are issues with the control of optoelectrical properties, low thiol passivation rate, and poor morphology with a power conversion efficiency (PCE) of approximately 11%. Although polymeric HTMs have been introduced to address these issues, maximizing efficiency and achieving green‐solvent processability and thermal stability for commercialization is necessary. Here, we synthesize a novel benzodifuran (BDF)‐based HTM (asy‐ranPBTBDF) showing an electron‐deficient state, low steric hindrance, and low planarity compared to those of a typical benzodithiophene (BDT)‐based HTM (asy‐ranPBTBDT). BDF properties lead to deep high occupied molecular orbital (HOMO) levels, close π–π stacking, excellent solubility, and amorphous properties related to efficiency, green‐solvent processability, and thermal stability. With these benefits, the asy‐ranPBTBDF‐based CQD‐SC showed enhanced open‐circuit voltage (VOC) (0.65 V) and PCE (13.29%) compared to those of the asy‐ranPBTBDT‐based device (0.63 V and 12.22%) in toxic processes with chlorobenzene. The asy‐ranPBTBDF‐based CQD‐SC showed a PCE of 12.51% in a green‐solvent process with 2‐methylanisole and improved thermal stability at 80 °C (83.8% retaining after 24 h) owing to less lateral crystallization than the asy‐ranPBTBDT‐based device (60.8% retaining after 24 h). [ABSTRACT FROM AUTHOR]

Derived from electric double‐layer capacitors (EDLCs), capacitive deionization (CDI) using symmetric carbon‐based electrodes is an emerging approach to purifying brackish water into drinking water. The deionization performance is mainly determined by the properties of the electrode materials. This work reports a green and efficient plasma treatment for activating raw biochar, which is subsequently used as the electrode material for both EDLCs and CDI. Oxygen plasma activation effectively modulates the surface charge, morphology, and functional groups. Biochar treated with oxygen plasma exhibits pronounced improvement in supercapacitor specific capacitance from 80 to 97.5 F g−1 and 1.2 times higher desalination capacity in comparison with the raw biochar. Plasma activation can be an effective strategy to improving the capacitance and deionization performance of biochar. [ABSTRACT FROM AUTHOR]

Recently, as state‐of‐the‐art displays, wearable electronic devices and free‐form displays have begun to attract attention to the point that much research on textile‐based displays has been actively conducted as an ultimate platform for wearable displays. However, although many studies have reported organic light‐emitting diodes (OLEDs) as the most suitable type for textile‐based displays due to their high opto‐electronic performance and flexibility, most research on textile‐based OLEDs (textile OLEDs) has left for the future improvements that require the use of transparent OLEDs (trOLEDs) for applications where aesthetics are important, such as fashion displays and automobile interiors. Herein, RGB‐color trOLEDs are designed using a dielectric‐metal‐dielectric transparent electrode to overcome the limitations of previous works on textile‐based non‐transparent OLEDs and to improve the aesthetic elements of textile displays. The opto‐electronic performance and the mechanical characteristics of textile RGB trOLEDs are analyzed, and specifically, this study suggests a new method and a novel equation for an optical analysis to quantify the clarity of printed color images (i.e., information) on a textile substrate when trOLEDs on the textile substrate are not operated, as needed to optimize and maximize the aesthetic elements of textile displays. [ABSTRACT FROM AUTHOR]

Antisolvent treatment has been developed to effectively fabricate dimethylammonium‐iodide (DMAI)‐assisted CsPbI3 perovskite solar cells (PSC) under moisture conditions. However, a clear understanding of its effect on the crystallization mechanism is still elusive. Here, the antisolvent bathing effect on DMAI‐assisted CsPbI3 crystallization is investigated under ambient conditions. For films bathed into antisolvents with Lewis basic oxygen (i.e., diethyl ether, anisole, ethyl acetate, and methyl acetate), rapid crystallization kinetics are observed due to the interaction between Cs4PbI6 and antisolvent in the form of the adduct. The Cs4PbI6‐antisolvent adduct lowers the transformation energy barrier, thereby enabling immediate phase transformation to CsPbI3 as soon as DMAPbI3 is decomposed. Based on this observation, a new crystallization mechanism is proposed for DMAI‐assisted CsPbI3 in which Cs4PbI6, instead of DMAPbI3, plays the role of the predominant phase of crystallization. Accelerated crystallization due to anisole antisolvent bathing results in a uniform film morphology and better coverage with fewer defects and pinholes. This enhances the power conversion efficiency of the n‐i‐p‐structured PSCs based on anisole‐bathed CsPbI3 to 18.84%, even under moisture conditions. [ABSTRACT FROM AUTHOR]

Smart displays have been integrated into our daily life, providing new concepts of interconnections between humans and interactivity with close collaboration between users. As a centerpiece of this integration, textile displays that can be worn like clothes are being intensively developed and are poised to provide a more intimate and closer connection. Among various light sources that have been used in the field of textile displays, organic light‐emitting diodes (OLEDs) have attracted considerable attention as one of the promising candidates for realizing truly wearable textile displays (i.e., wearing displays) in that they have shown the highest level of technical maturity, including high optoelectronic performance and flexibility, which can provide not only clear visual information and versatility regardless of the surrounding environment but have also been industrially proven. This review introduces the recent progress in OLED‐based textile displays and related technologies, with the discussion of challenges and limitations of the fiber‐ and fabric‐based approaches. Additionally, specific opinions are provided on research opportunities for organic light‐emitting textile displays, which can contribute to realizing truly wearable textile displays with a complete platform in the future. [ABSTRACT FROM AUTHOR]

We demonstrate color‐tunable organic light‐emitting diodes (OLEDs) with a red, green, and blue emission material deposited on an ultra‐thin textile platform. It secures similar performance to glass‐based OLEDs and proves the potential of a true wearable fashion display. [ABSTRACT FROM AUTHOR]

Light‐emitting fibers have been intensively developed for the realization of textile displays and various lighting applications, as promising free‐form electronics with outstanding interconnectivity. These advances in the fiber displays have been made possible by the successful implementation of the core technologies of conventional displays, including high optoelectronic performance and essential elements, in the fiber form‐factor. However, although white organic light‐emitting diodes (WOLEDs), as a fundamental core technology of displays, are essential for realizing full‐color displays and solid‐state lighting, fiber‐based WOLEDs are still challenging due to structural issues and the lack of approaches to implementing WOLEDs on fiber. Herein, the first fiber WOLED is reported, exhibiting high optoelectronic performance and a reliable color index, comparable to those of conventional planar WOLEDs. As key features, it is found that WOLEDs can be successfully introduced on a cylindrical fiber using a dip‐coatable single white‐emission layer based on simulation and optimization of the white spectra. Furthermore, to ensure durability from usage, the fiber WOLED is encapsulated by an Al2O3/elastomer bilayer, showing stable operation under repetitive bending and pressure, and in water. This pioneering work is believed to provide building blocks for realizing complete textile display technologies by complementing the lack of the core technology. [ABSTRACT FROM AUTHOR]

Next‐generation solution‐processed solar cells will hopefully be processed using green solvents, and will unite high performance with operating stability. Colloidal quantum dot/polymer hybrid solar cells are of interest for their harvest of the visible as well as the near infrared; however, today's best polymer hole‐transporting layers (HTLs) rely on processing using hazardous solvents such as chlorobenzene. This stems from the strong polymer–polymer attraction in polymeric p‐type materials, which accounts for their limited solubility. Here, a new random polymeric HTL (asy‐ranPBTBDT) is reported that is soluble in green solvents such as 2‐methylanisole without compromising ultimate device power conversion efficiency. The new polymer structure induces a strong π–π stacking face‐on orientation and less lateral grain growth compared to control asy‐PBTBDT, leading to reduced charge recombination and improved device stability. The resulting device exhibits a power conversion efficiency (PCE) of 13.2% and retains 89% of its initial efficiency after 120 h of continuous device operation at the maximum power point, compared to a PCE of 11.4% and 71% degradation for control devices. [ABSTRACT FROM AUTHOR]

With the recent developments in the efficiency of perovskite solar cells (PSCs), diverse functionalities are necessary for next‐generation charge‐transport layers. Specifically, the hole‐transport layer (HTL) in the various synthesized materials modified with functional groups is explored. A novel donor–acceptor type polymer, alkoxy‐PTEG, composed of benzo[1,2‐b:4,5:b′]dithiophene and tetraethylene glycol (TEG)‐substituted 2,1,3‐benzothiadiazole is reported. The alkoxy‐PTEG exhibits high solubility even in nonaromatic solvents, such as 3‐methylcyclohexanone (3‐MC), and can prevent possible lead leakage via chelation. The optical and electronic properties of alkoxy‐PTEG are thoroughly analyzed. Finally, a dopant‐free alkoxy‐PTEG device processed with 3‐MC exhibits 19.9% efficiency and a device with 2‐methyl anisole, which is a reported aromatic food additive, exhibits 21.2% efficiency in a tin oxide planar structure. The PSC device shows 88% stability after 30 d at ambient conditions (40–50% relative humidity and room temperature). In addition, nuclear magnetic resonance reveals that TEG groups can chelate lead ions with moderate strength (Kbinding = 2.76), and this strength is considered to be nondestructive to the perovskite lattice to prevent lead leakage. This is the first report to consider lead leakage and provide solutions to reduce this problem. [ABSTRACT FROM AUTHOR]

With the application of organic–inorganic hybrid perovskites to liquid‐type solar cells, the unprecedented development of perovskite solar cells (Per‐SCs) has been boosted by the introduction of solid‐state hole transport materials (HTMs). The removal of liquid electrolyte has lead to improved efficiency and stability. Supported by high‐quality perovskite films, the certified efficiency of Per‐SCs has reached 25.2%. For Per‐SCs assembled in a conventional structure (n–i–p), the hole transport layer (HTL) plays an extra role in preventing the perovskite layer from external stimuli. In summary, the successful design and fabrication of the HTL must meet various requirements in terms of solubility, hole transport, recombination prevention, stability, and reproducibility, to name but a few. Many research strategies are focused on the development of high‐performance HTMs to meet such requirements. Such strategies for the development of HTMs employed in conventional n–i–p solar cells are reviewed herein. A vision of the future HTMs is proposed in this review based on the already proposed solutions and current trends. [ABSTRACT FROM AUTHOR]

Abstract: Organic–inorganic hybrid perovskite has led to the development of new solar cells with outstanding efficiency. In perovskite solar cells (PSCs), perovskite is sandwiched between a working electrode (fluorine‐doped tin oxide) and a counter electrode (gold, Au). In order to transport charges and block opposite charges, charge transport layers are inserted between perovskite and the electrodes. In particular, a hole transport layer is important because it generally prevents perovskite from exposure to air. Therefore, it is necessary to investigate dopant‐free and hydrophobic polymeric hole transport materials (HTMs). In this study, a novel polymeric HTM (PTEG) is synthesized by controlling the solubility using a tetraethylene glycol group. The planar‐PSC employing PTEG exhibits an efficiency of 19.8% without any dopants, which corresponds to the highest value reported to date. This study offers a fundamental strategy for designing and synthesizing various polymeric HTMs. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article I Organic Light-Emitting Fibers and Fabrics for Truly Wearable Smart Displays: Recent Progress and Future Opportunities i by Yong Ha Hwang et al., https://doi.org/10.1002/jsid.1164. [Extracted from the article]

Porous titanium dioxide with an average pore diameter of several nanometers and a narrow pore size distribution was prepared by using cyclodextrin ( CD) in a sol-gel reaction of titanium precursor. After the reaction, a hydrothermal treatment was performed, and a WAXD analysis shows that the hydrothermal treatment successfully induces an anatase crystalline structure in TiO2 . The combined results from TGA, FT-IR, N2 adsorption-desorption isotherm, TEM, and SEM analyses show that the CD act as a pore forming template to form TiO2 with a wormhole-type pore and a large specific surface area. Furthermore, the ratio of the CD/Ti precursor affects the porosity and the morphology of the mesoporous TiO2 . In contrast, TiO2 prepared without CD does not exhibit a porous structure. The formation of these porous structures is a result of the self-assembly of Ti species around the CD molecules, TiO2 growth, and pore-forming by the removal of CD. [ABSTRACT FROM AUTHOR]

The positioning of the nucleosome by ATP-dependent remodellers provides the fundamental chromatin environment for the regulation of diverse cellular processes acting on the underlying DNA. Recently, genome-wide nucleosome mapping has revealed more detailed information on the chromatin-remodelling factors. Here, we report that the Schizosaccharomyces pombe CHD remodeller, Hrp3, is a global regulator that drives proper nucleosome positioning and nucleosome stability. The loss of Hrp3 resulted in nucleosome perturbation across the chromosome, and the production of antisense transcripts in the hrp3? cells emphasized the importance of nucleosome architecture for proper transcription. Notably, perturbation of the nucleosome in hrp3 deletion mutant was also associated with destabilization of the DNA-histone interaction and cell cycle-dependent alleviation of heterochromatin silencing. Furthermore, the effect of Hrp3 in the pericentric region was found to be accomplished via a physical interaction with Swi6, and appeared to cooperate with other heterochromatin factors for gene silencing. Taken together, our data indicate that a well-positioned nucleosome by Hrp3 is important for the spatial-temporal control of transcription-associated processes. [ABSTRACT FROM AUTHOR]

Clothing‐type, textile‐based OLEDs and their bio‐medical application have been investigated. Textile‐based OLEDs have shown wide applicability and washability as well as high flexibility for a wearing textile displays. Furthermore, a novel phototherapy for neonatal jaundice by using textile‐OLEDs was proposed in this work. [ABSTRACT FROM AUTHOR]

Chiral perovskites are promising materials due to their unique ability to interact with circularly polarized light (CPL), offering great potential in advanced photonic and spintronic applications. However, specific design principles for highly chiroptically active chiral perovskites remain unclear, hindering their practical exploitation. In this study, chiral cation fluorinated isomerization approach is employed to enhance the chiroptical response of chiral perovskites. Specifically, it is systematically discovered that incorporating ortho‐fluorinated chiral cations instead of para‐fluorinated cations induces a strong organic–inorganic halogen–halogen interaction due to the unique spatial arrangement. This boosted chirality transfer, mediated by the strong halogen–halogen interaction, resulting in a fivefold improvement in the circular dichroism compared to its para‐fluorinated counterpart. Consequently, a CPL photodetector utilizing the ortho‐fluorinated chiral perovskite exhibited superior CPL distinguishability of 0.288, the highest value among 2D lead‐iodide perovskite‐based devices. Furthermore, the photodetector incorporating these structural isomers demonstrated extended operational stability as well as high photodetecting performance. [ABSTRACT FROM AUTHOR]

Organic Photovoltaics: Study of Burn-In Loss in Green Solvent-Processed Ternary Blended Organic Photovoltaics Derived from UV-Crosslinkable Semiconducting Polymers and Nonfullerene Acceptors (Adv. In article number 1901829, Jin Young Kim, Taiho Park and co-workers report that cross-linkable semiconducting polymers and nonfullerene acceptors can lead to thermal stability in a green-solvent processed organic photovoltaic. The burn-in loss due to thermal aging and light soaking is dramatically suppressed due to the frozen morphology from the cross-linkable polymers and high miscibility from the nonfullerene acceptors. [Extracted from the article]

This work deals with the investigation of burn‐in loss in ternary blended organic photovoltaics (OPVs) prepared from a UV‐crosslinkable semiconducting polymer (P2FBTT‐Br) and a nonfullerene acceptor (IEICO‐4F) via a green solvent process. The synthesized P2FBTT‐Br can be crosslinked by UV irradiation for 150 s and dissolved in 2‐methylanisole due to its asymmetric structure. In OPV performance and burn‐in loss tests performed at 75 °C or AM 1.5G Sun illumination for 90 h, UV‐crosslinked devices with PC71BM show 9.2% power conversion efficiency (PCE) and better stability against burn‐in loss than pristine devices. The frozen morphology resulting from the crosslinking prevents lateral crystallization and aggregation related to morphological degradation. When IEICO‐4F is introduced in place of a fullerene‐based acceptor, the burn‐in loss due to thermal aging and light soaking is dramatically suppressed because of the frozen morphology and high miscibility of the nonfullerene acceptor (18.7% → 90.8% after 90 h at 75 °C and 37.9% → 77.5% after 90 h at AM 1.5G). The resulting crosslinked device shows 9.4% PCE (9.8% in chlorobenzene), which is the highest value reported to date for crosslinked active materials, in the first green processing approach. [ABSTRACT FROM AUTHOR]