The electrochemical reduction reaction of carbon dioxide (CO2RR) to carbon monoxide (CO) is the basis for the further synthesis of more complex carbon-based fuels or attractive feedstock. Single-atom catalysts have unique electronic and geometric structures with respect to their bulk counterparts, thus exhibiting unexpected catalytic activities. A nitrogen-anchored Zn single-atom catalyst is presented for CO formation from CO2RR with high catalytic activity (onset overpotential down to 24 mV), high selectivity (Faradaic efficiency for CO (FE ) up to 95 % at -0.43 V), remarkable durability (>75 h without decay of FE ), and large turnover frequency (TOF, up to 9969 h ). Further experimental and DFT results indicate that the four-nitrogen-anchored Zn single atom (Zn-N ) is the main active site for CO2RR with low free energy barrier for the formation of *COOH as the rate-limiting step.

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The development of high‐efficiency electrocatalysts for large‐scale water splitting is critical but also challenging. In this study, a hierarchical CoMoSx chalcogel was synthesized on a nickel foam (NF) through an in situ metathesis reaction and demonstrated excellent activity and stability in the electrocatalytic hydrogen evolution reaction and oxygen evolution reaction in alkaline media. The high catalytic activity could be ascribed to the abundant active sites/defects in the amorphous framework and promotion of activity through cobalt doping. Furthermore, the superhydrophilicity and superaerophobicity of micro‐/nanostructured CoMoSx/NF promoted mass transfer by facilitating access of electrolytes and ensuring fast release of gas bubbles. By employing CoMoSx/NF as bifunctional electrocatalysts, the overall water splitting device delivered a current density of 500 mA cm−2 at a low voltage of 1.89 V and maintained its activity without decay for 100 h.

Maximizing the platinum utilization in electrocatalysts toward oxygen reduction reaction (ORR) is very desirable for large‐scale sustainable application of Pt in energy systems. A cost‐effective carbon‐supported carbon‐defect‐anchored platinum single‐atom electrocatalysts (Pt1/C) with remarkable ORR performance is reported. An acidic H2/O2 single cell with Pt1/C as cathode delivers a maximum power density of 520 mW cm−2 at 80 °C, corresponding to a superhigh platinum utilization of 0.09 gPt kW−1. Further physical characterization and density functional theory computations reveal that single Pt atoms anchored stably by four carbon atoms in carbon divacancies (Pt‐C4) are the main active centers for the observed high ORR performance.

Strong metal–support interaction (SMSI) has been regarded as one of the most important concepts in heterogeneous catalysis, which has been almost exclusively discussed in metal/oxide catalysts. Here, we show that gold/molybdenum carbide (Au/MoC x ) catalysts feature highly dispersed Au overlayers, strong interfacial charge transfer between metal and support, and excellent activity in the low-temperature water–gas shift reaction (LT-WGSR), demonstrating the active SMSI state. Subsequent oxidation treatment results in strong aggregation of Au nanoparticles, weak interfacial electronic interaction, and poor LT-WGSR activity. The two interface states can be transformed into each other by alternative carbonization and oxidation treatments. This work reveals the active SMSI effect in metal/carbide catalysts induced by carbonization, which opens a new territory for this important concept.

Tuning local spin state of Co centres by Fe doping in cobalt–iron selenides is effective for boosting oxygen evolution.

Metal nanoparticle (NP), cluster and isolated metal atom (or single atom, SA) exhibit different catalytic performance in heterogeneous catalysis originating from their distinct nanostructures. To maximize atom efficiency and boost activity for catalysis, the construction of structure–performance relationship provides an effective way at the atomic level. Here, we successfully fabricate fully exposed Pt3 clusters on the defective nanodiamond@graphene (ND@G) by the assistance of atomically dispersed Sn promoters, and correlated the n-butane direct dehydrogenation (DDH) activity with the average coordination number (CN) of Pt-Pt bond in Pt NP, Pt3 cluster and Pt SA for fundamentally understanding structure (especially the sub-nano structure) effects on n-butane DDH reaction at the atomic level. The as-prepared fully exposed Pt3 cluster catalyst shows higher conversion (35.4%) and remarkable alkene selectivity (99.0%) for n-butane direct DDH reaction at 450 °C, compared to typical Pt NP and Pt SA catalysts supported on ND@G. Density functional theory calculation (DFT) reveal that the fully exposed Pt3 clusters possess favorable dehydrogenation activation barrier of n-butane and reasonable desorption barrier of butene in the DDH reaction.

Electrochemical reduction of carbon dioxide (CO2) is a promising approach to solve both renewable energy storage and carbon‐neutral energy cycles, while the capability of selective reduction to C2+ products has still been quite limited. In this work, partially reduced copper oxide nanodendrites with rich surface oxygen vacancies (CuOx–Vo) are developed, serving as excellent Lewis base sites for enhanced CO2 adsorption and subsequent electrochemical reduction. Theoretical calculations reveal that these oxygen vacancy‐rich CuOx surfaces provide strong binding affinities to the intermediates of *CO and *COH, but weak affinity to *CH2, thus leading to efficient formation of C2H4. As a result, the partially reduced CuOx nanodendrites exhibit one of the highest C2H4 production Faradaic efficiencies of 63%. The electrochemical stability test further shows that the C2H4 Faradaic efficiency strongly depends on the oxygen vacancy density in CuOx, which can further be regenerated for several cycles, thus suggesting the critical role of oxygen vacancies for the C2 product selectivity.