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Electrocatalytic CO2 reduction to value-added hydrocarbon products using metallic copper (Cu) catalysts is a potentially sustainable approach to facilitate carbon neutrality. However, Cu metal suffers from unavoidable and uncontrollable surface reconstruction during electrocatalysis, which can have either adverse or beneficial effects on its electrocatalytic performance. In a break from the current catalyst design path, we propose a strategy guiding the reconstruction process in a favorable direction to improve the performance. Typically, the controlled surface reconstruction is facilely realized using an electrolyte additive, ethylenediamine tetramethylenephosphonic acid, to substantially promote CO2 electroreduction to CH4 for commercial polycrystalline Cu. As a result, a stable CH4 Faradaic efficiency of 64% with a partial current density of 192 mA cm−2, thus enabling an impressive CO2-to-CH4 conversion rate of 0.25 µmol cm−2 s−1, is achieved in an alkaline flow cell. We believe our study will promote the exploration of electrochemical reconstruction and provide a promising route for the discovery of high-performance electrocatalysts.

By carefully controlling the kinds and sites of the B or N dopant, graphdiyne can be utilized as a metal-free electrocatalyst with high-efficiency and high selectivity for CO2 reduction to C1 and C2 products.

The light-driven CO 2 reduction to multicarbon products is especially meaningful, while the low efficiency of multi-electron transfer and sluggish CÀ C coupling greatly hinder its development. Herein, we report a photocatalyst comprising of P and Cu dual sites anchored on graphitic carbon nitride (P/Cu SAs@CN), which achieves a high C 2 H 6 evolution rate of 616.6 μmol g À 1 h À 1 in reducing CO 2 to hydrocarbons. The detailed spectroscopic characterizations identify the formation of charge-enriched Cu sites, where the isolated P atoms serve as hole capture sites during photocatalysis. Theoretical simulations combined with in situ FTIR measurement reveal a kinetically feasible process for the formation of CÀ C coupling intermediate (*OCÀ COH) and confirm the favorable production of C 2 H 6 on the P/Cu SAs@CN photocatalyst. This work offers new insights into the photocatalyst design with atomic precision toward highly efficient photocatalytic CO 2 conversion to high value-added carbon products.

Large-scale ammonia synthesis via the electrochemical nitrogen reduction reaction (eNRR) under mild reaction conditions represents a green prospect for agriculture, industry, and energy. This bioinspired and carbon-free reaction has been proposed as an ideal alternative to the Haber–Bosch process. However, the yield and selectivity of the current eNRR have not met the requirements for industrialization. Mechanistic understanding and catalysts’ design are still long-term pursuits in this field, where theoretical simulations will have significant contributions. In this Review, we will start with the natural N2 fixation enzymes, the nitrogenases, followed by a summary of the key experimental eNRR performances on hundreds of recently reported catalysts, and we analyze the general trend and challenges before eNRR can significantly impact the ammonia industry. Then, we will systematically review the recent progress and contributions of computational studies in understanding the reaction mechanism and rational catalyst design for eNRR. The fundamental principles, reaction mechanisms, crucial theoretical criteria, modeling methods, and computationally predicted catalysts for eNRR are systematically summarized and discussed. Finally, we outline the current challenges and future opportunities for experimental and computational studies of electrochemical N2 reduction.

Surface and strain engineering are two effective strategies to improve performance; however, synergetic controls of surface and strain effects remains a grand challenge. Herein, we report a highly efficient and stable electrocatalyst with defect-rich Pt atomic layers coating an ordered Pt3Sn intermetallic core. Pt atomic layers enable the generation of 4.4% tensile strain along the [001] direction. Benefiting from synergetic controls of surface and strain engineering, Pt atomic-layer catalyst (Ptatomic‑layer) achieves a remarkable enhancement on ethanol electrooxidation performance with excellent specific activity of 5.83 mA cm–2 and mass activity of 1166.6 mA mg Pt –1, which is 10.6 and 3.6 times higher than the commercial Pt/C, respectively. Moreover, the intermetallic core endows Ptatomic‑layer with outstanding durability. In situ infrared reflection–absorption spectroscopy as well as density functional theory calculations reveal that tensile strain and rich defects of Ptatomci‑layer facilitate to break C–C bond for complete ethanol oxidation for enhanced performance.

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Designed metal-free electrocatalysts combined with compressive strain can efficiently convert CO to valuable chemicals and fuels.