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Solar-driven conversion of bicarbonate (HCO3−) to carbonaceous fuels and/or chemicals provides an alternative route for the development of sustainable carbon economies. However, promoting the HCO3− reduction rate and tuning product selectivity remain significant challenges. This study reports the identification of isolated Ni/Cu atomic pairs dispersed on a BiOCl surface (Ni1/Cu1-BOC) as a promising candidate for efficient HCO3− reduction under UV-vis light irradiation. The optimized photocatalyst exhibits a high CO formation rate of 157.1 μmol g−1 h−1 with nearly 100% selectivity, even in the absence of added proton sources, sacrificial agents, or sensitizers. Experimental and theoretical investigations reveal that the atomically dispersed Ni/Cu pairs facilitate the protonation of HCO3− to CO2, which then undergoes a H+-assisted reduction pathway to produce CO, with *COOH as the intermediate. The synergistic effects of the Ni/Cu atomic pairs simultaneously promote the HCO3−-to-CO2 conversion and the subsequent CO2-to-CO reduction, providing valuable insights for the development of efficient diatomic catalysts for photocatalytic HCO3− reduction reactions. [ABSTRACT FROM AUTHOR]

The key means to improve the performance of lithium–sulfur batteries (LSBs) is to reduce the internal resistance by building an electronic/ionic pathway and to accelerate the conversion kinetics of lithium polysulfides (LiPSs) through modulation of interface functions. Herein, inspired by a grass root system, a flexible hierarchical CNF‐CNT (carbon nanofiber‐carbon nanotube) membrane decorated with Co‐doped NiS2 nanoparticles (Co‐NiS2@CNF‐CNT) is designed as an interlayer for LSBs, in which the in situ grown CNTs (root hairs) are wound on CNF (roots). Density functional theory (DFT) calculations show that Co doping introduces electron‐deficient regions at the doping sites in NiS2, thus improving chemical adsorption and catalytic activities toward LiPSs. The cell pairs with the Co‐NiS2@CNF‐CNT interlayer exhibit a high rate performance of 951.4 mAh g−1 at 3 C, a reversible capacity of 944.1 mAh g−1 after 500 cycles at 0.2 C, and a prolonged cycle life of 3000 cycles at 5 C. More importantly, an areal capacity of 7.96 mAh cm−2 is achieved with a sulfur loading of 9.6 mg cm−2. This work provides a strategy for enhancing the electrochemical performance of LSBs by combining 3D hierarchical conductive skeletons and electron‐deficient functional adsorption and catalysis materials. [ABSTRACT FROM AUTHOR]

The development of Fe single‐atom catalysts (Fe SACs) with abundant, accessible Fe sites is a key step toward enhancing the efficiency of the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). In this study, Zn4O(1,4‐benzenedicarboxylate)3 (MOF‐5), which has a 3D microporous cubic structure, is used as the precursor to prepare highly‐porous carbon (denoted as C‐MOF‐5) with an ultrahigh specific surface area (2751 m2 g–1) and high external surface area (1651 m2 g–1). C‐MOF‐5 is demonstrated as an effective carbon support to yield Fe SAC‐MOF‐5 with a large amount of accessible FeNx sites (2.35 wt%). Fe SAC‐MOF‐5 delivers a half‐wave potential of 0.83 V (vs RHE) in a 0.5 m H2SO4 electrolyte, and achieves a peak power density of 0.84 W cm–2 in a 0.2 MPa H2‐O2 PEMFC. This excellent performance originates from the ultrahigh specific surface area of C‐MOF‐5 for the formation of a high density of single Fe atoms, and high external surface area for the increased exposure of active sites. This work may inspire the rational design of metal single‐atom catalysts derived from a wider range of MOF precursors with ultrahigh specific area to improve the performance of the oxygen reduction reaction in PEMFCs. [ABSTRACT FROM AUTHOR]