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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. [ABSTRACT FROM AUTHOR]

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]

As a half‐reaction in anion exchange membrane water electrolysis (AEMWE) technology, the hydrogen evolution reaction (HER) at the cathode is severely hindered by the sluggish reaction kinetics involved in additional water dissociation step, which results in large overpotentials and low energy conversion efficiency. Here, we develop a nano‐heterostructure composed of ultra‐thin W5N4 shells over Ni3N nanoparticles (Ni3N@W5N4) as efficient catalysts, in which built‐in interfacial electric field (BIEF) is created owing to the distinct lattice arrangements and work functions of biphasic metal nitrides. The BIEF facilitates the electron localization around the interface and enables high valence W and more exposed binding sites in the surface W5N4 shell for accelerating the water dissociation step, ultimately leading to a remarkable reduction in the energy barriers of RDS from 1.40 eV to 0.26 eV. Theoretical calculations and operando X‐ray absorption spectroscopy analysis results demonstrated that surface W5N4 serves as the active species for HER. Moreover, the ultra‐thin shell characteristics enable the optimized W5N4 with enhanced intrinsic catalytic activity to be fully exposed as active sites. Consequently, the Ni3N@W5N4 exhibits exceptional performance in alkaline HER (60 mV@10 mA cm−2) and remarkable long‐term stability (500 mA cm−2 for 100 hours). When employed as the cathode in the AEMWE device, the synthesized Ni3N@W5N4 demonstrates stable performance for 90 hours at a current density of 1 A cm−2. [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of carbon dioxide (CO 2 ) to methane (CH 4 ) represents a sustainable route for directly converting greenhouse gases into chemicals but poses a significant challenge in achieving high selectivity due to thermodynamic and kinetic limitations during the reaction process. This work establishes Ru-O V active sites on the surface of TiO 2 by anchoring coordination unsaturated Ru single-atoms, which stabilize crucial reaction intermediates and facilitate local mass transfer to achieve dual optimization of the thermodynamics and kinetics of the overall photocatalytic CO 2 reduction. Combining operando spectroscopy with density functional theory (DFT) calculations indicates that oxygen vacancies (O V ) inhibits the desorption of *CO, whereas Ru facilitates proton extraction. This configuration not only lowers the overall activation energy barrier but has also been engineered to serve as a selectivity switch, changing the reaction route to produce CH 4 instead of CO. Consequently, the Ru-O V /TiO 2 exhibits a 195.4-fold improvement in the CH 4 yield compared to TiO 2 , accompanied by an increase in selectivity to 81%., (© 2024 Wiley‐VCH GmbH.)

The sluggish anodic oxygen evolution reaction (OER) in proton exchange membrane (PEM) electrolysis necessitates applied bias to facilitate electron transfer as well as bond cleavage and formation. Traditional electrocatalysis focuses on analyzing the effects of electron transfer, while the role of charge accumulation induced by the applied overpotential has not been thoroughly investigated. To explore the influence mechanism of bias-driven charge accumulation, capacitive Mn is incorporated into IrO 2 to regulate the local electronic structure and the adsorption behavior. The applied bias triggers dynamic redox reactions at the active sites, which introduce local charge accumulation on the surface of electrocatalyst. Under bias, Mn oxidation induced a noticeable pseudocapacitance in the pre-OER region, promoting the OER kinetics of iridium sites. Meanwhile, the increased oxygen vacancy formation energy further prevents the lattice oxygen activation. The PEM electrolyzer, equipped with optimal materials as an anode, operates at a low driving voltage of 1.637 V under 2.0 A cm -2 , maintaining stable performance for over 800 h with a low degradation rate (19.4 µV h -1 ). This work provides insights into the performance of metal oxide catalysts in acidic environments and offers forward-looking strategies for enhancing the catalytic performance through dynamic redox induced capacitive behavior., (© 2024 Wiley‐VCH GmbH.)

Iridium (Ir)-based oxide is the state-of-the-art electrocatalyst for acidic water oxidation, yet it is restricted to a few Ir-O octahedral packing modes with limited structural flexibility. Herein, the geometric structure diversification of Ir is achieved by integrating spatially correlated Ir atoms into the surface lattice of TiO 2 and its booting effect on oxygen evolution reaction (OER) is investigated. Notably, the resultant i-Ir/TiO 2 catalyst exhibits much higher electrocatalytic activity, with an overpotential of 240 mV at 10 mA cm -2 and excellent stability of 315 h at 100 mA cm -2 in acidic electrolyte. Both experimental and theoretical findings reveal that flexible Ir─O─Ir coordination with varied geometric structure plays a crucial role in enhancing OER activity, which optimize the intermediate adsorption by adjusting the d-band center of active Ir sites. Operando characterizations demonstrate that the interactive Ir─O─Ir units can suppress over-oxidation of Ir, effectively widening the stable region of Ir species during the catalytic process. The proton exchange membrane (PEM) electrolyzer, equipped with i-Ir/TiO 2 as an anode, gives a low driving voltage of 1.63 V at 2 A cm -2 and maintains stable performance for over 440 h. This work presents a general strategy to eliminate the inherent geometric limitations of IrO x species, thereby inspiring further development of advanced catalyst designs., (© 2024 Wiley‐VCH GmbH.)