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This study explores the optimal morphology of photochemical hydrogen evolution catalysts in a one‐dimensional system. Systematic engineering of metal tips on precisely defined CdSe@CdS dot‐in‐rods is conducted to exert control over morphology, composition, and both factors. The outcome yields an optimized configuration, a Au−Pt core‐shell structure with a rough Pt surface (Au@r‐Pt), which exhibits a remarkable fivefold increase in quantum efficiency, reaching 86 % at 455 nm and superior hydrogen evolution rates under visible and AM1.5 G irradiation conditions with prolonged stability. Kinetic investigations using photoelectrochemical and time‐resolved measurements demonstrate a greater extent and extended lifetime of the charge‐separated state on the tips as well as rapid water reduction kinetics on high‐energy surfaces. This approach sheds light on the critical role of cocatalysts in hybrid photocatalytic systems for achieving high performance. [ABSTRACT FROM AUTHOR]

The identification and quantification of hydrogen (H)‐bonded complexes form the cornerstone of reaction‐mechanism analysis in ultrafast proton‐transfer reactions. Traditionally, the Benesi–Hildebrand method has been employed to obtain the formation constants of H‐bonded complexes, given that H‐bonding additives induce an alteration in spectral features exclusively through H‐bond formation. However, if the additive introduction impacts the bulk polarity of the solution, inducing a spectral shift, the spectroscopic method's accuracy in analyzing the H‐bond formation becomes compromised. In this study, we scrutinize H‐bond formation under the influence of an H‐bond accepting solute in an aprotic solvent. This is achieved by quantifying the fractions of two concurrent pathways involved in the excited‐state proton transfer (ESPT) of a super‐photoacid: the ultrafast ESPT of an H‐bonded complex versus the diffusion‐controlled ESPT of the free acid. Our method offers improved accuracy compared to conventional steady‐state spectroscopic techniques, by directly quantifying the H‐bonded complexes using the time‐resolved spectroscopic method, thereby circumventing the aforementioned limitation. [ABSTRACT FROM AUTHOR]

A new benzodithiophene (BDT) building block, 4,8-bis(5-(2-ethylhexyl)-3-fluoro-4-hexylthiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene (3-FBDT), was designed by tailoring the positions and number of alkyl and F substituents by adjusting the torsional energy barrier. The incorporation of 3-FBDT into a representative BDT-based polymer donor (PBDB-T-2F) yielded a new photovoltaic copolymer (PBDB-T-2F(3/4)) with a decreased valence band level and considerably improved solubility in non-halogenated and non-aromatic solvents such as tetrahydrofuran (THF). Side-chain engineering has been widely studied to control solution processability in eco-friendly solvents, but the torsional property control of conjugated main chains has rarely been attempted. Although PBDB-T-2F showed a significant drop in power conversion efficiencies (PCEs: 17.46 to 9.73%) owing to serious aggregation caused by replacing chloroform with THF as a processing solvent, the THF-processed PBDB-T-2F(3/4) device maintained a high PCE (14.3 to 13.86%) with little detrimental effect. Charge carrier dynamics and film morphology analyses suggested that the electronic and morphological properties of PBDB-T-2F(3/4) are mainly governed by the majority moiety of the PBDB-T-2F blocks. Owing to its high solubility and outstanding photoelectrical properties, PBDB-T-2F(3/4) was successfully employed to fabricate flexible, semi-transparent, and large-area THF-processed devices. The incorporation of the 3-FBDT building block into various BDT-based photovoltaic polymers can be an effective strategy to improve the solution processability and broaden the solvent selection for fabricating eco-friendly solar cells without significantly disrupting their photoelectrical properties. [ABSTRACT FROM AUTHOR]

Power conversion efficiencies (PCEs) of glove‐box (GB) processed, two‐component, single‐junction organic solar cells (OSCs) have recently exceeded 18%. However, their mass‐scale manufacture using roll‐to‐roll (R2R) coating techniques is impracticable if they must be fabricated in an air‐free environment. From a commercialization perspective, efficient air‐processed OSCs are of much greater interest than GB‐processed devices since the vast majority of R2R‐manufacturing infrastructure is designed to operate in the air. Herein, it is reported that controlling the crystallinity of non‐fullerene acceptors plays a key role in determining the properties of blend films. Notably, Y6‐hu (a Y6‐derivative) is shown to exhibits a higher degree of crystallinity when processed in air. Air‐processed OSCs show an outstanding PCE of 17.38%, which, to the best of the authors' knowledge, is the highest PCE yet reported for two‐component‐based OSCs processed in air using halogen‐free solvents. Moreover, opaque large‐area OSC sub‐modules with PCEs of 12.44%, and red‐green‐blue colored semi‐transparent OSC sub‐modules with PCEs of >10% are demonstrated. By understanding how morphological features relate to the charge‐generation dynamics of air‐processed OSCs, a new window is opened for the fabrication of efficient and stable air‐processable organic electronics. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is a very promising carbide material with various applications such as electrochemical supercapacitors, photocatalysis, microwave absorption, field-effect transistors, and sensors. Due to its enticing advantages of high thermal stability, outstanding chemical stability, high thermal conductivity, and excellent mechanical behavior, it is used as a potential candidate in various fields such as supercapacitors, water-splitting, photocatalysis, biomedical, sensors, and so on. This review mainly describes the various synthesis techniques of nanostructured SiC (0D, 1D, 2D, and 3D) and its properties. Thereafter, the ongoing research trends in electrochemical supercapacitor electrodes are fully excavated. Finally, the outlook of future research directions, key obstacles, and possible solutions are emphasized. [ABSTRACT FROM AUTHOR]

Electroluminescence efficiencies of deep-blue quasi-two-dimensional (quasi-2D) perovskites are limited by a lack of post-treatment strategies that can both construct an ideal energy-transfer tunnel structure minimizing the exciton losses and passivate chlorine vacancies. Herein, multi-functional halide post-exchange is demonstrated for fabricating efficient deep-blue quasi-2D perovskite light-emitting diodes (PeLEDs). This post-treatment suppresses detrimental chlorine vacancies in the perovskite lattice, resulting in an efficient deep-blue perovskite emitter. Synergistically, the spontaneous phase rearrangement occurs via merging between neighboring low-n phases to higher-n phases. The narrowed 2D phase distribution enhances excitonic-energy transfer to the target bulk phase with fewer energy transfer steps, each of which is accompanied by adverse energy loss by exciton dissociation. Efficient deep-blue PeLEDs with a maximum external quantum efficiency of 4.97% are realized, emitting at 470 nm. Device lifetimes are also elongated as a synergetic benefit. This work provides an effective approach as a step closer to designing high-performance deep-blue PeLEDs for practical applications. [ABSTRACT FROM AUTHOR]

Reusing or recycling waste into new useful materials is essential for environmental protection. Herein, we used discarded polystyrene (PS) and fly-ash (FA) particles and a fabricated fly-ash incorporated polystyrene fiber (FA/PS fiber) composite. The electrospinning process produced continuous PS fibers with a good distribution of FA particles. The prepared nanofibers were characterized by state-of-the-art techniques. The performances of the composite nanofibers were tested for fire-retardant applications. We observed that the incorporation of FA particles into the PS fibers led to an improvement in the performance of the composite as compared to the pristine PS fibers. This study showed an important strategy in using waste materials to produce functional nanofibers through an economical procedure. We believe that the strategy presented in this paper can be extended to other waste materials for obtaining nanofiber membranes for various environmental applications. [ABSTRACT FROM AUTHOR]

The key to current Alzheimer's disease (AD) therapy is the early diagnosis for prompt intervention, since available treatments only slow the disease progression. Therefore, this lack of promising therapies has called for diagnostic screening tests to identify those likely to develop full-blown AD. Recent AD diagnosis guidelines incorporated core biomarker analyses into criteria, including amyloid-β (Aβ), total-tau (T-tau), and phosphorylated tau (P-tau). Though effective, the accessibility of screening tests involving conventional cerebrospinal fluid (CSF)- and blood-based analyses is often hindered by the invasiveness and high cost. In an attempt to overcome these shortcomings, biomarker profiling research using non-invasive body fluid has shown the potential to capture the pathological changes in the patients' bodies. These novel non-invasive body fluid biomarkers for AD have emerged as diagnostic and pathological targets. Here, we review the potential peripheral biomarkers, including non-invasive peripheral body fluids of nasal discharge, tear, saliva, and urine for AD. [ABSTRACT FROM AUTHOR]

Base treatment and metal doping were evaluated as means of enhancing the photocatalytic activity of ZrO2 nanoparticles (NPs) via the generation of oxygen vacancies (OvS), and the sites responsible for this enhancement were identified and characterized by spectroscopic and microscopic techniques. We confirmed that OvS produced by base treatment engaged in photocatalytic activity for organic pollutant degradation, whereas surface defects introduced by Cr-ion doping engaged in oxidative catalysis of molecules. Moreover, we verified that base-treated ZrO2 NPs outperformed their Cr-ion doped counterparts as photocatalysts using in situ X-ray photoelectron spectroscopy and scanning transmission electron microscopy coupled with electron energy loss spectroscopy (STEM-EELS). Thus, our study provides valuable information on the origin of the enhanced photocatalytic activity of modified ZrO2 NPs and demonstrates the practicality of in situ spectroscopy and STEM-EELS for the evaluation of highly efficient metal oxide photocatalysts. [ABSTRACT FROM AUTHOR]

The excited‐state proton transfer (ESPT) of the strong photoacid, N‐methyl‐7‐hydroxyquinolium (NM7HQ+), was studied in the presence of N‐methylbenzamide (NMB) as a base in the aprotic polar solvent, acetonitrile. According to the Benesi–Hildebrand relation, it was revealed that the hydrogen (H)‐bonded complex of NM7HQ+ and NMB exists in the ground state in a 1:1 stoichiometry with the association constant of 22.2 ± 1.7 M−1. The fluorescence quenching of the 1:1 complex was observed to follow the Stern–Volmer relation with the molecularity of one for NMB indicating that the ESPT of NM7HQ+ occurs with the H‐bonded chain of two NMB molecules. Our study highlights the cooperative nature of H‐bonding in the chemical reactivity of amide in acid–base reactions as has already been reported for alcohol. [ABSTRACT FROM AUTHOR]