Authors: Wenli Sun, Shilong Liu, Hongfei Sun, Hongyan Hu, Jiazhou Li, Lingzhi Wei, Ziqi Tian, Qianwang Chen, Jianwei Su, Liang Chen
Published: 2025-03-23
Source: Full article
AbstractIn essence, electrocatalytic CO2 reduction reaction (CO2RR) process for the CO2‐to‐CO conversion involves two critical reactive intermediates: *COOH and *CO. The trade‐off between the adsorption of *COOH and the desorption of *CO is challenging for Ni‐based CO2RR catalysts. The high‐valence Ni site is inadequate in supplying sufficient electrons for CO2 activation and subsequent adsorption of *COOH; conversely, the metallic Ni site with abundant electron exhibits excessively strong π‐backbonding with *CO, thus hindering its desorption. Here, the study reports a low‐coordinated Ni single atom catalyst (SAC) characterized by a low‐coordinated structure with carbon coordination, thereby engineering a moderate electron depletion at its Ni sites. This Ni SAC achieves a high selectivity for CO production up to 99.1% in H‐cell. Additionally, it maintains an ultrahigh CO selectivity near 100% across a broad range of current densities in flow cell, coupled with sustained stability at a large current of 250 mA cm−2 for 20 h. Both in situ characterization results and density functional theory (DFT) calculations confirm the dual functionality of this low‐coordinated structure, as it enhances the adsorption of *COOH while concurrently facilitating the subsequent desorption of *CO, thus greatly promoting the overall CO2RR process.