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The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high‐performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry‐breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT‐1SO. The asymmetric structure of BBTT‐1SO proved beneficial for increasing multiple moment and polarizability. BBTT‐1SO‐containing polymers showed higher efficiencies for hydrogen evolution than their DBS‐containing counterparts by up to 166 %. PBBTT‐1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g−1 h−1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT‐1SO‐based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT‐1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water‐PBBTT‐1SO polymer interactions in salt‐containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high‐performance photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

This study investigates the impact of crises caused by pandemics on firms' R&D investments. We explore these associations by utilizing a comprehensive cross-country sample of 261,959 firm-year observations collected from 39 countries during five modern health crises (SARS in 2003, H1N1 in 2009, MERS in 2012, Ebola in 2012, and Zika in 2016). The results indicate that pandemics have a positive and significant impact on R&D investment. Furthermore, we show that private firms in civil-law countries were more likely to adopt conservative financial policies than those in common-law countries. We conclude that the difference between the legal origins of private firms influences the impact on R&D investment. Moreover, it promotes conservative policies to reduce private firms' R&D investment in countries with civil law. [ABSTRACT FROM AUTHOR]

The escalating global scarcity of water resources has amplified the need to develop efficient desalination methods. Electrochemical deionization (ECDI) has emerged as a promising method to solve this pressing issue. Among various ECDI systems, conducting polymers have showcased remarkable potential for electrode materials due to their facile large-scale synthesis and precise control over the removal of anions and cations. We scrutinized the impact of diverse dopant sizes on the intrinsic properties of polypyrrole (PPy) chains, leading to the development of a high-performance ECDI system. Incorporation of para-substituted groups featuring elongated carbon chains, such as dodecylbenzene sulfonate (DBS), the PPy-DBS-1//PPy-ClO4 configuration attained a salt-adsorption capacity (SAC) of 61.7 mg g−1 in NaCl solution (10 mM) and sustained low energy consumption (0.22 kW h/kg-NaCl). Our findings suggest that the size and type of dopant have key roles in enhancing the ion transport and mobility of charge carriers within the conducting-polymer framework. Moreover, fine-tuning the doping ratio enhanced the cation-capture ability of electrodes and sustained their cycling stability. Overall, these insights into the symbiotic relationship between dopants and PPy framework within an ECDI system provide guidance framework for augmenting the electrode performance of conducting polymers with dopants, and expanding the potential applications of conducting polymers in ECDI. [ABSTRACT FROM AUTHOR]

The electrochemical nitrogen reduction reaction (NRR) is an attractive process for next‐generation ammonia synthesis; therefore, identifying a suitable catalyst for this reaction is critical. In recent years, transition‐metal dichalcogenides (TMDs) and their Janus structures have gained significant attention because of their outstanding catalytic properties. However, the synthesis of Janus TMDs remains challenging, and exposing their active sites is difficult when using a low‐dimensional structure to improve the catalytic activity. To date, relatively little research has been conducted in this area. Herein, emerging Janus WSeS/WSe2 heterostructure nanowalls are systematically explored. These nanowalls are used as a nitrogen fixation catalyst in electrolytes. The nanowalls demonstrate a significant NH3 yield rate and Faradaic efficiency of 13.97 µg h‐mgcat−1 and 35.24% at −0.3 V in 0.1 m HCl, as well as 15.96 µg h‐mgcat−1 and 40.2% in 0.1 M Na2SO4. This study presents an in‐depth analysis of the properties of Janus WSeS/WSe2 heterostructure nanowalls and a conceptual framework for linking TMD‐based catalysts and the NRR. [ABSTRACT FROM AUTHOR]

This study discusses the impact of executives with foreign experience on decisions involving corporate capital structures. Based on a sample of Chinese A-share listed companies, this study finds that firms with (more) executives with foreign experience adjust to the optimal capital structure faster. The effect exists mainly for over-levered firms that need to deleverage. The empirical results remain robust when using alternative methods to estimate target leverage, excluding the effects of mechanical adjustments, controlling the impact of corporate governance, and using the full sample to test asymmetric effects. In addition, firms managed by executives with foreign experience tend to maintain low leverage for a long time. Overall, the results show that executives with foreign experience help companies adopt more efficient and conservative capital structure adjustment decisions. The results enrich the literature on the impact of foreign experience on corporate decision-making. [ABSTRACT FROM AUTHOR]

A digital-to-analog converter (DAC) with small-size non-cascoded current cells is proposed to achieve small area, low-power consumption, and high linearity over a wide bandwidth. An output impedance compensation (OIC) technique using a compensation resistor, implemented by a PMOS with code-dependent gate voltage control, is proposed to remedy the nonlinearity induced by the insufficient output impedance of the non-cascoded current cells. In addition, a proposed concentric parallelogram routing (CPR) technique, in which the subcells of each current cell are arranged such that they form a parallelogram shape with a common centroid, is used to reduce both the mismatch error and the routing-induced timing skew among the current cells. The DAC, implemented in a 28-nm CMOS process, achieves >65-dBc spurious-free dynamic range (SFDR) and < −70-dBc third-order intermodulation distortion (IM3) over the entire Nyquist bandwidth at 10 GS/s while consuming 162 mW from a single 1.1 V supply. [ABSTRACT FROM AUTHOR]