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Developing atomically dispersed metal on nitrogen‐doped carbon (M─N─C) catalyst provides a promising strategy to convert CO2 into high‐valued chemicals and achieve artificially closed carbon cycles. However, it is challenging to tune the structure and coordination of N─M bond that further improve the intrinsic activity and selectivity of CO2RR. Herein, CuNi atomic clusters embedded in Ni/Cu dual atomic sites catalysts (CuNiAC@Ni/Cu─N─C) are designed and successfully manipulated to regulate the coordination environment for M─N─C catalysts to enhance the CO2 electroreduction reaction (CO2RR). The most active configuration in CuNiAC@Ni/Cu─N─C catalyst is CuNi atomic cluster connected with 2N‐bridged (Ni‐Cu)N5, in which two N atoms are shared with NiN4 and CuN3 moieties verified by both systematic advanced characterizations and density function theory (DFT) calculations. The results have revealed the integration between CuNi atomic cluster and N4Ni/CuN3 dual‐metal atomic sites that optimize the electronic redistribution and narrow the bandgap, thereby decreasing the energy barrier of the potential determination step and promoting CO production. [ABSTRACT FROM AUTHOR]

Cathode electrocatalysts with rich active sites are indispensable for achieving the superior performance of zinc–air batteries (ZABs). However, the integration of both oxygen reduction reaction and oxygen evolution reaction (ORR and OER) catalytic active sites poses challenges due to their opposite catalytic mechanisms. Besides, a mass of highly oxidizing intermediates generated by the OER site would attack the adjacent ORR active sites. Herein, a bottom-up strategy is developed to catenate the Co and FeCo beads onto the needle carbon connexons, wherein the FeCo alloys undergo self-reconstruction into FeOOH and Co-(OH)2 to facilitate the OER, while the separated Co nanoparticles play a crucial role in promoting the ORR. The FeCoAL&CoNP/NC Janus material exhibits significant potential in stabilizing its bifunctional oxygen electrocatalytic properties, bestowing rechargeable ZABs with long cycling stability (752 h) as the air–cathode catalyst. This study paves a pathway for the precise manipulation of the distribution of distinct active sites and selective control over oxygen electrocatalysts. [ABSTRACT FROM AUTHOR]

The development of efficient and low‐cost bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is imperative but remains challenging in rechargeable zinc–air batteries. Herein, a metal oxidation‐assisted approach is developed for the facile synthesis of a highly efficient bifunctional catalyst (Co@NC@LDHs) which is composed of layered double hydroxides (LDHs) nanosheets in situ vertically grown on the surface of hollow carbon nanoframes encapsulating Co nanoparticles (Co@NC). Specifically, the vertical LDHs distributing on the carbon surface ensure the maximized number of accessible active sites and the interaction between LDHs with the carbon matrix. The hierarchically structured bifunctional Co@NC@LDHs display an overpotential of 0.33 V at 10 mA cm−2 for OER and a half‐wave potential of 0.88 V for ORR. The potential gap (ΔE) of Co@NC@LDHs is calculated to be 0.68 V, outperforming the mixed Pt/C + RuO2 catalysts (ΔE = 0.77 V), manifesting its superior bifunctional electrocatalysis performance. Moreover, the Zn–air batteries based on Co@NC@LDHs electrocatalyst exhibit a high peak power density (185.2 mW cm−2) and excellent durability (5.0 mA cm−2 over 500 h). This work may provide a facile strategy for the fabrication of LDHs on carbon substrate, acting as efficient catalysts for broad energy‐related applications. [ABSTRACT FROM AUTHOR]

Engineering the surface structure of semiconductor is one of the most promising strategies for improving the separation and transfer efficiency of charge, which is a key issue in photocatalysis. Here, we designed and fabricated the C decorated hollow TiO2 photocatalysts (C–TiO2), in which 3-aminophenol-formaldehyde resin (APF) spheres were used as template and carbon precursor. It was determined that the C content can be easily controlled by calcinating the APF spheres with different time. Moreover, the synergetic effort between the optimal C content and the formed Ti–O–C bonds in C–TiO2 were determined to increase the light absorption and greatly promote the separation and transfer of charge in the photocatalytic reaction, which is verified from UV–vis, PL, photocurrent, and EIS characterizations. Remarkably, the activity of the C–TiO2 is 5.5-fold higher than that of TiO2 in H2 evolution. A feasible strategy for rational design and construction of surface-engineered hollow photocatalysts to improve the photocatalytic performance was provided in this study. [ABSTRACT FROM AUTHOR]