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Immobilizing platinum (Pt) single atoms on appropriate supports with optimized coordination environments and electronic structures is a promising strategy to address the problem of chlorine corrosion during seawater electrolysis. Herein, Pt single atoms on nickel‐vanadium layered double hydroxides (Pt‐SA/NiV‐LDH) matrix are fabricated for chlorine tolerance hydrogen generation. Due to the strong synergetic electronic interaction between atomically dispersed Pt and the ultrathin NiV LDH matrix, the adsorption/dissociation feature of *H2O, *OH, and *H are optimized as evidenced theoretically. The as‐fabricated Pt‐SA/NiV‐LDH electrode exhibits an exceptional mass activity (i.e., 30.98 times higher) compared to the commercial Pt/C, along with an ultra‐high turnover frequency (TOF) value of 9.90 s−1 in alkaline media. Impressively, only 207 mV overpotential is required to yield a current density of 2000 mA cm‒2 in an electrolyte solution containing 1 m KOH and 2 M NaCl, indicating its robust resistance to chlorine. Moreover, this kind of material demonstrates remarkably low overpotentials of 130 and 215 mV to attain the industrial‐scale current densities of 1000 and 2000 mA cm−2 in alkaline seawater, accompanied by exceptional stability for 500 h working at 500 mA cm−2. This work provides an insightful reference for the production of sustainable green hydrogen through seawater electrolysis. [ABSTRACT FROM AUTHOR]

Engineering oxygen vacancies (Vo) in metal–organic framework (MOF) is considered as an effective strategy to improve the hydrazine oxidation reaction (HzOR) performance. However, the role of Vo and the metal sites for HzOR is still not fully understood. Herein, this study reports the synthesis of a well‐defined bimetallic VO‐rich benzene dicarboxylic acid‐based MOF (NiIr0.03‐BDC) as a model to clarify the intricate catalytic mechanism. Operando characterizations demonstrate that the Vo‐rich environment favors the adsorption of OH− on the catalyst surface during the HzOR process, leading to the formation of Ni(OH)x active species. Theoretical calculations reveal that the introduced Ir at metal nodes not only boosts the HzOR activity of the Ni sites by tuning their electronic structure but also serves as the active sites for hydrogen evolution. As a result, the two‐electrode electrolyzer with NiIr0.03‐BDC || NiIr0.03‐BDC configuration achieved 10 mA cm−2 at an ultralow cell voltage of 0.046 V. This work provides new insights into oxygen vacancy defect engineering of MOFs and paves a solid step for low‐energy consumption hydrogen production. [ABSTRACT FROM AUTHOR]

A N, S co‐doped carbon with abundant vacancy defects (NSC) anchored Pt single atoms (SAs) and nanoclusters (NCs) derived from coal pitch by a self‐assembly‐pyrolysis strategy is reported and a defect‐induced electron redistribution effect based on Pt SAs‐Pt NCs/NSC catalyst is proposed for electrocatalytic hydrogen evolution reaction (HER). The optimized catalyst featuring Pt‐N3S1 SAs and Pt NCs dual active sites exhibit excellent HER activity with an overpotential of 192 mV at a current density of 400 mA cm−2, a turnover frequency of 30.1 s−1 at an overpotential of 150 mV, which the mass activity is 13716 mA mgPt−1, 7.4 times higher than that of 20% Pt/C catalyst. In situ Raman revealsa direct correlation between the defect structure of the catalyst and hydrogen adsorption during the reaction process. Density functional theory calculation shows the defect‐induced electron redistribution between Pt‐N3S1 SAs and Pt NCs. The electrons are transferred from Pt NCs to Pt SAs, which increases the number of electrons on the surface of Pt SAs and enhances the adsorption ability of H+. Meanwhile, the dissociation ability of H* on the Pt NCs is promoted, thus synergistically promoting the HER process. [ABSTRACT FROM AUTHOR]

One challenge for realizing high-efficiency electrocatalysts for CO2 electroreduction is lacking in comprehensive understanding of potential-driven chemical state and dynamic atomic-configuration evolutions. Herein, by using a complementary combination of in situ/operando methods and employing copper single-atom electrocatalyst as a model system, we provide evidence on how the complex interplay among dynamic atomic-configuration, chemical state change and surface coulombic charging determines the resulting product profiles. We further demonstrate an informative indicator of atomic surface charge (φe) for evaluating the CO2RR performance, and validate potential-driven dynamic low-coordinated Cu centers for performing significantly high selectivity and activity toward CO product over the well-known four N-coordinated counterparts. It indicates that the structural reconstruction only involved the dynamic breaking of Cu–N bond is partially reversible, whereas Cu–Cu bond formation is clearly irreversible. For all single-atom electrocatalysts (Cu, Fe and Co), the φe value for efficient CO production has been revealed closely correlated with the configuration transformation to generate dynamic low-coordinated configuration. A universal explication can be concluded that the dynamic low-coordinated configuration is the active form to efficiently catalyze CO2-to-CO conversion. Comprehensive understanding of Cu state is of high interest for CO2 electroconversion. Here, the authors reveal a dynamic low-coordinated Cu center as active site for CO2 to CO conversion and propose atomic surface charge as an indicator for evaluating CO2 electroreduction performance. [ABSTRACT FROM AUTHOR]

This study adopts a facile and effective in situ encapsulation‐oxidation strategy for constructing a coupling catalyst composed of atomically dispersed Pt‐doped Co3O4 spinel nanoparticles (NPs) embedded in polyhedron frames (PFs) for robust propane total oxidation. Benefiting from the abundant oxygen vacancies and more highly valent active Co3+ species caused by the doping of Pt atoms as well as the confinement effect, the optimized 0.2Pt‐Co3O4 NPs/PFs catalyst exhibits excellent propane catalytic activity with low T90 (184 °C), superior apparent reaction rate (21.62×108 (mol gcat−1 s−1)), low apparent activation energy (Ea = 17.89 kJ mol−1), high turnover frequency (811×107 (mol gcat−1 s−1)) as well as good stability. In situ diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculations indicate that the doping of Pt atoms enhances the oxygen activation ability, and decreases the energy barrier required for CH bond breaking, thus improving the deep oxidation process of the intermediate species. This study opens up new ideas for constructing coupling catalysts from atomic scale with low cost to enhance the activation of oxygen molecules and the deep oxidation of linear short chain alkanes at low temperature. [ABSTRACT FROM AUTHOR]