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Understanding the correlation between the structural evolution of electrocatalysts and their catalytic activity is both essential and challenging. In this study, we investigate this correlation in the context of the oxygen evolution reaction (OER) by examining the influence of structural disorder during and after dynamic structural evolution on the OER activity of Fe−Ni (oxy)hydroxide catalysts using operando X‐ray absorption spectroscopy, alongside other experiments and theoretical calculations. The Debye–Waller factors obtained from extended X‐ray absorption fine structure analyses reflect the degree of structural disorder and exhibit a robust correlation with the intrinsic OER activities of the electrocatalysts. The enhanced OER activity of in situ‐generated metal (oxy)hydroxides derived from different pre‐catalysts is linked to increased structural disorder, offering a promising approach for designing efficient OER electrocatalysts. This strategy may inspire similar investigations in related electrocatalytic energy‐conversion systems. [ABSTRACT FROM AUTHOR]

Core‐shell nanocolloids with tailored physical and chemical merits hold attractive potential for energy‐related applications. Herein, core‐shell nanocolloids composed of zinc/copper sulfide (ZnS/CuSx) shells and silica (SiO2) cores were fabricated by a template‐engaged synthetic method. Interestingly, the sizes of SiO2 cores can be tuned by different sulfurization time. In virtue of the light scattering and reflection on the SiO2 surface, the efficiencies of light capture by ZnS/Cu2S shells were highly dependent on the SiO2 sizes. The as‐fabricated SiO2@ZnS/Cu2S with a core size of 205 nm exhibited the highest and broadest absorption within a light wavelength of 380–700 nm. In virtue of the structural and componential features of these nanocolloids, maximum photocatalytic hydrogen (H2) production rates of 2968 and 1824 μmol h−1 g−1 under UV‐vis and visible light have been delivered, respectively. This work may provide some evidence for the design and fabrication of core‐shell nanomaterials to convert solar energy to green fuels. [ABSTRACT FROM AUTHOR]

Copper‐doped ZnS/ZnO (CSO) hexahedrons in egg tart‐like morphology were fabricated by an in‐situ synthetic strategy to promote photocatalytic hydrogen (H2) production. Hexahedral CuO/ZnO precursors in micro sizes were prepared by a solvothermal method. A subsequent moderate sulfurization of the precursor led to the formation of ZnS/ZnO heterostructures without alteration of the hexahedral morphology. In addition, the in‐situ methodology ensured the homogeneous doping of copper species with ZnS/ZnO heterostructures, which significantly improved the electric conductivity of these hybrid materials. Because of the structural and compositional features of the hybrid materials, a maximum H2 production rate of 1.044 mmol g−1 h−1 with high recycling stability (even after 12 h) has been delivered based on an interfacial catalysis. Thus, this study may provide an efficient strategy to optimize the physical and chemical properties of photocatalysts in microsize scale. [ABSTRACT FROM AUTHOR]

Cover Feature: In-situ Copper Doping with ZnO/ZnS Heterostructures to Promote Interfacial Photocatalysis of Microsized Particles (2/2021) Keywords: Photocatalysis; ZnS/ZnO; Heterostructure; In-situ copper doping; Solar energy EN Photocatalysis ZnS/ZnO Heterostructure In-situ copper doping Solar energy 489 489 1 01/28/21 20210120 NES 210120 B The Cover Feature b shows a little cat looking at a microsized particle which is like an egg tart. Photocatalysis, ZnS/ZnO, Heterostructure, In-situ copper doping, Solar energy. [Extracted from the article]

Chemical modification via functional dopants in carbon materials holds great promise for elevating catalytic activity and stability. To gain comprehensive insights into the pivotal mechanisms and establish structure-performance relationships, especially concerning the roles of dopants, remains a pressing need. Herein, we employ computational simulations to unravel the catalytic function of heteroatoms in the acidic oxygen evolution reaction (OER), focusing on a physical model of high-electronegative F and N co-doped carbon matrix. Theoretical and experimental findings elucidate that the enhanced activity originates from the F and pyridinic-N (Py-N) species that achieve carbon activation. This activated carbon significantly lowers the conversion energy barrier from O* to OOH*, shifts the potential-limiting step from OOH* formation to O* generation, and ultimately optimizes the energy barrier of the potential-limiting step. This wok elucidates that the critical role of heteroatoms in catalyzing the reaction and unlocks the potential of carbon materials for acidic OER., (© 2024 Wiley‐VCH GmbH.)

Understanding the correlation between the structural evolution of electrocatalysts and their catalytic activity is both essential and challenging. In this study, we investigate this correlation in the context of the oxygen evolution reaction (OER) by examining the influence of structural disorder during and after dynamic structural evolution on the OER activity of Fe-Ni (oxy)hydroxide catalysts using operando X-ray absorption spectroscopy, alongside other experiments and theoretical calculations. The Debye-Waller factors obtained from extended X-ray absorption fine structure analyses reflect the degree of structural disorder and exhibit a robust correlation with the intrinsic OER activities of the electrocatalysts. The enhanced OER activity of in situ-generated metal (oxy)hydroxides derived from different pre-catalysts is linked to increased structural disorder, offering a promising approach for designing efficient OER electrocatalysts. This strategy may inspire similar investigations in related electrocatalytic energy-conversion systems., (© 2023 Wiley-VCH GmbH.)

The solar-driven evolution of hydrogen from water using particulate photocatalysts is considered one of the most economical and promising protocols for achieving a stable supply of renewable energy. However, the efficiency of photocatalytic water splitting is far from satisfactory due to the sluggish electron-hole pair separation kinetics. Herein, isolated Mo atoms in a high oxidation state have been incorporated into the lattice of Cd 0.5 Zn 0.5 S (CZS@Mo) nanorods, which exhibit photocatalytic hydrogen evolution rate of 11.32 mmol g -1  h -1 (226.4 μmol h -1 ; catalyst dosage 20 mg). Experimental and theoretical simulation results imply that the highly oxidized Mo species lead to mobile-charge imbalances in CZS and induce the directional photogenerated electrons transfer, resulting in effectively inhibited electron-hole recombination and greatly enhanced photocatalytic efficiency., (© 2023 Wiley-VCH GmbH.)