The development of heterogeneous catalysts with a well-defined micro structure to promote their activity and stability for electrocatalytic CO₂ reduction has been shown to be a promising strategy. In this work, Cu nanoparticles (∼ 4 nm in diameter) embedded in N-doped carbon (Cu@NC) arrays were fabricated by thermal decomposition of copper tetracyanoquinodimethane (CuTCNQ) under N₂. Compared to polycrystalline copper electrodes, the Cu@NC arrays provide a significantly improved number of catalytically active sites. This resulted in a 0.7 V positive shift in onset potential, producing a catalytic current density an order magnitude larger at a potential of–2.7 V vs. Fc/Fc⁺ (Fc = ferrocene) in dimethylformamide (DMF). By controlling the water content in the DMF solvent, the CO₂ reduction product distribution can be tuned. Under optimal conditions (0.5 vol% water), 64% HCOO^–, 20% CO, and 13% H₂ were obtained. The Cu@NC arrays exhibited excellent catalytic stability with only a 0.5% decrease in the steady-state catalytic current during 6 h of electrolysis. The three-dimensional (3D) array structure of the Cu@NC was demonstrated to be effective for improving the catalytic activity of copper based catalysts while maintaining long-term catalytic stability.

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已经开发出具有明确定义的微观结构以提高其活性和电催化还原CO ₂稳定性的非均相催化剂是一种有前途的策略。在这项工作中，通过在N ₂下对四氰基喹_二甲烷铜（CuTCNQ）进行热分解，制备了嵌入N掺杂碳（Cu @ NC）阵列中的Cu纳米粒子（直径约4 nm）。与多晶铜电极相比，Cu @ NC阵列可显着提高催化活性位的数量。这导致起始电势有0.7 V的正移，在–2.7 V的电势下，与Fc / Fc ⁺相比，产生的催化电流密度大一个数量级。（Fc =二茂铁）在二甲基甲酰胺（DMF）中。通过控制DMF溶剂中的水含量，可以调整CO ₂还原产物的分布。在最佳条件下（0.5％的水），可获得64％的HCOO ^–，20％的CO和13％的H ₂。Cu @ NC阵列表现出出色的催化稳定性，在电解6小时期间，稳态催化电流仅降低了0.5％。事实证明，Cu @ NC的三维（3D）阵列结构可有效提高铜基催化剂的催化活性，同时保持长期的催化稳定性。

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