Carbon nanotubes (CNTs)‐supported metal‐based catalysts applied in the electrochemical reduction of CO₂ (CO₂ER) have attracted extensive research recently. Nevertheless, insight into the roles of surface oxygen functional groups in these catalysts on CO₂ER is still deficient. Herein, three catalysts were reasonably fabricated by chemically loading Ag nanoparticles (NPs) on the oxygenic CNTs (CNT−COOH, CNT−OH and CNT−CO) with precise tuning oxygen functional groups, and then used to explore the effect of oxygen functional groups on the electrocatalytic performance of Ag NPs for CO₂ER. Compared with the other two counterparts, Ag/CNT−COOH with the highest content of carboxyl groups possesses the most uniform size and dispersion of Ag NPs and the strongest surface acidic environment, which enable it to exhibit the highest current density and Faradaic efficiency for CO production at high overpotential region (E≤−1.0 V vs. RHE). This work broadens the understanding of surface oxygen functional groups of catalysts in enhancing CO₂ER performance, and provides guidance for the design and synthesis of high‐performance catalysts.

中文翻译：

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氧官能团在碳纳米管负载的Ag催化剂中的作用，以将CO2电化学转化为CO

碳纳米管（CNTs）负载的金属基催化剂在电化学还原CO ₂（CO ₂ ER）中得到了广泛的应用。然而，仍然缺乏关于表面氧官能团在这些催化剂上对CO ₂ ER的作用的认识。本文中，通过将Ag纳米颗粒（NPs）化学负载在具有精确调节氧官能团的含氧CNTs（CNT-COOH，CNT-OH和CNT-CO）上，合理地制备了三种催化剂纳米碳纳米管对CO ₂的电催化性能ER。与其他两个对应物相比，具有最高羧基含量的Ag / CNT-COOH具有最均匀的Ag NP尺寸和分散性以及最强的表面酸性环境，从而使其表现出最高的电流密度和法拉第效率。在高过电势区域（E ≤−1.0 V vs. RHE）下生产。这项工作拓宽了在增强CO ₂ ER性能方面催化剂表面氧官能团的认识，并为高性能催化剂的设计和合成提供了指导。