Unveiling hydrocerussite as an electrochemically stable active phase for efficient carbon dioxide electroreduction to formate
Yanmei Shi, Ji Yan, Jun Long, Liang Yu, Yang Liu, Yifu Yu, Jianping Xiao, Bin Zhang
Abstract
Abstract For most metal-containing CO 2 reduction reaction (CO 2 RR) electrocatalysts, the unavoidable self-reduction to zero-valence metal will promote hydrogen evolution, hence lowering the CO 2 RR selectivity. Thus it is challenging to design a stable phase with resistance to electrochemical self-reduction as well as high CO 2 RR activity. Herein, we report a scenario to develop hydrocerussite as a stable and active electrocatalyst via in situ conversion of a complex precursor, tannin-lead(II) (TA-Pb) complex. A comprehensive characterization reveals the in situ transformation of TA-Pb to cerussite (PbCO 3 ), and sequentially to hydrocerussite (Pb 3 (CO 3 ) 2 (OH) 2 ), which finally serves as a stable and active phase under CO 2 RR condition. Both experiments and theoretical calculations confirm the high activity and selectivity over hydrocerussite. This work not only offers a new approach of enhancing the selectivity in CO 2 RR by suppressing the self-reduction of electrode materials, but also provides a strategy for studying the reaction mechanism and active phases of electrocatalysts.