Potential-Driven Restructuring of Cu Single Atoms to Nanoparticles for Boosting the Electrochemical Reduction of Nitrate to Ammonia
作者:Ji Yang、Haifeng Qi、Anqi Li、Xiaoyan Liu、Xiaofeng Yang、Shengxin Zhang、Qiao Zhao、Qike Jiang、Yang Su、Leilei Zhang、Jian-Feng Li、Zhong-Qun Tian、Wei Liu、Aiqin Wang、Tao Zhang
DOI:10.1021/jacs.2c02262
日期:2022.7.13
disintegrated into single atoms and then restored to the Cu–N4 structure upon being exposed to an ambient atmosphere, which masks the potential-induced restructuring during the reaction. The synchronous changes of the Cu0 percentage and the ammonia Faradaic efficiency with the applied potential suggests that the Cu nanoparticles are the genuine active sites for nitrate reduction to ammonia, which is corroborated
重构在热催化中无处不在,对于识别真正的活性位点至关重要,但在电催化中却很少有人探索。在此,通过使用原位X 射线吸收光谱和先进的电子显微镜,我们揭示了在硝酸盐电化学还原为氨的过程中,合成的 Cu-N 4单原子位点重组为约 5 nm 的纳米颗粒,与氮的等离子体辅助氧化相结合的绿色氨生产路线。发现Cu 2+还原为Cu +和Cu 0以及随后Cu 0单原子的聚集与NH 3的增强同时发生。生产率,它们都是由施加的电位从 0.00 切换到 -1.00 V 与 RHE 驱动的。氨的最大产率达到 4.5 mg cm –2 h –1 (12.5 mol NH 3 g Cu –1 h –1 ),在 -1.00 V 时法拉第效率与 RHE 相比为 84.7%,优于已报道的大多数其他 Cu 催化剂之前。电解后,聚集的 Cu 纳米粒子可逆地分解成单个原子,然后在暴露于环境大气时恢复为 Cu-N 4结构,这掩盖了反应过程中电位诱导的重组。Cu