Autophagy is a crucial quality control mechanism that degrades damaged cellular components through lysosomal fusion with autophagosomes. However, elevated autophagy levels can promote drug resistance in cancer cells, enhancing their survival. Downregulation of autophagy through oxidative stress is a clinically promising strategy to counteract drug resistance, yet precise control of oxidative stress in autophagic proteins remains challenging.
View Article and Find Full Text PDFImproving the hydroxide conductivity and dimensional stability of anion exchange membranes (AEMs) while retaining their high alkaline stability is necessary to realize the commercialization of AEM water electrolysis (AEMWE). A strategy for improving the hydroxide conductivity and dimensional stability of AEMs by inserting fluorine atoms in the core structure of the backbone is reported, which not only reduces the glass transition temperature of the polymer due to steric strain, but also induces distinct phase separation by inducing polarity discrimination to facilitate the formation of ion transport channels. The resulting PFPFTP-QA AEM with fluorine into the core structure shows high hydroxide conductivity (>159 mS cm at 80 °C), favorable dimensional stability (>25% at 80 °C), and excellent alkaline stability for 1000 h in 2 m KOH solution at 80 °C.
View Article and Find Full Text PDFTo achieve the global goal of carbon neutrality, recently, emphasis has been placed on developing green ammonia production method to replace the Haber-Bosch process. Nitrate reduction reaction (NO RR) has received considerable attention, especially for electrochemically producing ammonia from nitrate and simultaneously purifying wastewater. This study first demonstrates that the combination of NO RR with hydrazine oxidation reaction (HzOR) is an energy efficient green ammonia production method, which overcomes the sluggish water oxidation limitation.
View Article and Find Full Text PDFThe advancement of non-fullerene acceptors with crescent-shaped geometry has led to the need for polymer donor improvements. Additionally, there is potential to enhance the photovoltaic parameters in high-efficiency organic solar cells (OSCs). The random copolymerization method is a straightforward and effective strategy to further optimize photoactive morphology and enhance device performance.
View Article and Find Full Text PDFRecently, multijunction tandem solar cells (TSCs) have presented high power conversion efficiency and revealed their immense potential in photovoltaic evolution. It is demonstrated that multiple light absorbers with various bandgap energies overcome the Shockley-Queisser limit of single-junction solar cells by absorbing the wide-range wavelength photons. Here, the main key challenges are reviewed, especially the charge carrier dynamics in perovskite-based 2-terminal (2-T) TSCs in terms of current matching, and how to manage these issues from a vantage point of characterization.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2023
High thermal stability is crucial for the commercialization of organic solar cells (OSCs). The thermal stability of OSCs has been improved using the tailoring blend morphology of bulk heterojunctions (BHJs). Herein, we demonstrated thermally stable OSCs in a ternary blended system containing low-crystalline semiconducting polymers ( and PTB7-Th) and a non-fullerene acceptor (Y6).
View Article and Find Full Text PDFElectroadhesion provides a promising route to augment robotic functionalities with continuous, astrictive, and reversible adhesion force. However, the lack of suitable conductive/dielectric materials and processing capabilities have impeded the integration of electroadhesive modules into soft robots requiring both mechanical compliance and robustness. We present herein an iontronic adhesive based on a dynamically crosslinked gel-elastomer system, including an ionic organohydrogel as adhesive electrodes and a resilient polyurethane with high electrostatic energy density as dielectric layers.
View Article and Find Full Text PDFThree new cationic cyclometalated iridium(III) complexes equipped with differently substituted benzo[]thiophen-2-ylquinoline cyclometalating ligands and with a sterically demanding -butyl-substituted 2,2'-bipyridine ancillary ligand were synthesized and structurally characterized by NMR and X-ray diffraction techniques. To tune the electronic properties of such complexes, the quinoline moiety of the cyclometalating ligands was kept pristine or equipped with electron-withdrawing phenyl and -CF substituents, leading to complexes , , and , respectively. A complete electrochemical and photophysical investigation, supported by density functional theory calculations, permits a deep understanding of their electronic properties.
View Article and Find Full Text PDFPerovskite quantum dots (PQDs) have been considered promising and effective photovoltaic absorber due to their superior optoelectronic properties and inherent material merits combining perovskites and QDs. However, they exhibit low moisture stability at room humidity (20-30%) owing to many surface defect sites generated by inefficient ligand exchange process. These surface traps must be re-passivated to improve both charge transport ability and moisture stability.
View Article and Find Full Text PDFThe power conversion efficiency of CsPbI perovskite quantum dot (PQD) solar cells shows increase from 10.77% to 16.2% in a short period owing to advances in material and device design for solar cells.
View Article and Find Full Text PDFDefect passivation has become essential in improving efficiency and stability in perovskite solar cells. Here, we report the use of (α-methylguanido)acetic acid, also known as creatine, as a passivation molecule. It is employed both as an additive and as a surface passivation layer of perovskite thin films, given its multiple functional groups, which could address different defect sites, and its size, which could inherently affect the material structure.
View Article and Find Full Text PDFDefects and energy offsets at the bulk and heterojunction interfaces of perovskite are detrimental to the efficiency and stability of perovskite solar cells (PSCs). Herein, we designed an amphiphilic π-conjugated ionic compound (QAPyBF ), implementing simultaneous defects passivation and interface energy level alignments. The p-type conjugated cations passivated the surface trap states and optimized energy alignment at the perovskite/hole transport layer.
View Article and Find Full Text PDFOrganic photovoltaics (OPVs) have emerged as a promising next-generation technology with great potential for portable, wearable, and transparent photovoltaic applications. Over the past few decades, remarkable advances have been made in non-fullerene acceptor (NFA)-based OPVs, with their power conversion efficiency exceeding 18%, which is close to the requirements for commercial realization. Novel molecular NFA designs have emerged and evolved in the progress of understanding the physical features of NFA-based OPVs in relation to their high performance, while there is room for further improvement.
View Article and Find Full Text PDFOrganic photovoltaics (OPVs) are a promising next-generation photovoltaic technology with great potential for wearable and transparent device applications. Over the past decades, remarkable advances in device efficiency close to 20 % have been made for bulk heterojunction (BHJ)-based OPV devices with long-term stability, and room for further improvements still exists. In recent years, ancillary components have been demonstrated as effective in improving the photovoltaic performance of OPVs by controlling the optoelectronic and morphological properties of BHJ blends.
View Article and Find Full Text PDFThe effects of the microstructure of conjugated polymer thin films on charge trapping and operational stability of organic field-effect transistors (OFETs) are investigated. Device characteristics of OFETs based on two model conjugated polymers, poly(3-hexylthiophene) (P3HT) and a random 3-hexylthiophene-thiophene copolymer (RP33), are compared. P3HT films have high crystallinity and long-range molecular order, whereas RP33 films have low crystallinity and short-range molecular order as well as enhanced polymer backbone planarity.
View Article and Find Full Text PDFThe need for optoelectronic and chemical compatibility between the layers in colloidal quantum dot (CQD) photovoltaic devices remains a bottleneck in further increasing performance. Conjugated polymers are promising candidates as new hole-transport layer (HTL) materials in CQD solar cells (CQD-SCs) owing to the highly tunable optoelectronic properties and compatible chemistries. A diketopyrrolopyrrole-based polymer with benzothiadiazole derivatives (PD2FCT-29DPP) as an HTL in these devices is reported.
View Article and Find Full Text PDFQuantum dots (QDs) are emerging photovoltaic materials that display exclusive characteristics that can be adjusted through modification of their size and surface chemistry. However, designing a QD-based optoelectronic device requires specialized approaches compared with designing conventional bulk-based solar cells. In this paper, design considerations for QD thin-film solar cells are introduced from two different viewpoints: optics and electrics.
View Article and Find Full Text PDFMonolithically integrated hybrid tandem solar cells (TSCs) that combine solution-processed colloidal quantum dot (CQD) and organic molecules are a promising device architecture, able to complement the absorption across the visible to the infrared. However, the performance of organic/CQD hybrid TSCs has not yet surpassed that of single-junction CQD solar cells. Here, a strategic optical structure is devised to overcome the prior performance limit of hybrid TSCs by employing a multibuffer layer and a dual near-infrared (NIR) absorber.
View Article and Find Full Text PDFFor emerging biocompatible, wearable, and stretchable epidermal electronic devices, it is essential to realize novel stretchable conductors with the attributes of transparency, low-cost and nontoxic components, green-solvent processbility, self-healing, and thermal stabililty. Although conducting materials-rubber composites, ionic hydrogels, organogels have been developed, no stretchable material system that meets all the outlined requirements has been reported. Here, a series of P(SPMA-r-MMA) polymers with different ratios of ionic side chains is designed and synthesized, and it is demonstrated that the resulting stretchable ionic conductors with glycerol are transparent, water processable, self-healable, and thermally stable due to the chemically linked ionic side chain, satisfying all of the aforementioned requirements.
View Article and Find Full Text PDFComplementary water splitting electrocatalysts used simultaneously in the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) can simplify water splitting systems. Herein, earth-abundant NiMoFe (NMF) and phosphorized NiMoFeP (NMFP) are synthesized as complementary overall water splitting (OWS) catalysts. First, NMF is tested as both the HER and OER promoter, which exhibits low overpotentials of 68 (HER) and 337 mV (OER).
View Article and Find Full Text PDFHerein, poly(3-hexylthiophene) films with periodic wavy surface structures are generated upon laser irradiation at a wavelength of 530 nm using a pulse duration of 5 ns and a repetition frequency of 10 Hz. The optical properties of the films irradiated with 1200, 3000, and 6000 pulses, respectively, are studied using various techniques.
View Article and Find Full Text PDFNumerous previous studies have focused on the notion that semiconducting polymers with an edge-on dominant orientation are advantageous for horizontal charge transport, whereas polymers with a face-on dominant orientation are advantageous for vertical charge transport, since the crystallite orientation determines the π-π stacking direction, which in turn affects the interchain charge transport direction. Here, we report that the crystallite orientation is dependent on the intermolecular interactions in the semiconducting polymer. In this study, we control the intermolecular interactions in a donor-acceptor (D-A) semiconducting polymer via side chain engineering.
View Article and Find Full Text PDFThe aging of propellants in PMDs is considered to be one of the primary factors affecting the performance of PMDs. Thus, studies on the aging mechanism of propellants, which have not yet been addressed extensively, pose a solution to securing the sustainable operation of PMDs. We characterized one of the most commonly used commercial propellants (boron potassium nitrate (BKNO)) and investigated its aging mechanism rigorously.
View Article and Find Full Text PDFTo understand how disorder within conjugated polymer aggregates influences the polaron generation process, we investigated poly(3-hexylthiophene) (P3HT) and a congeneric random copolymer incorporating 33 mol % substituent-free thiophene units (RP33). Steady-state absorption and fluorescence spectra showed that increasing the intrachain torsional disorder in aggregates increases the energy and breadth of the density of states (DOS). By extracting polaron dynamics in the transient absorption spectra, we found that an activation energy barrier of 0.
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