Reconstructing Cu Nanoparticle Supported on Vertical Graphene Surfaces via Electrochemical Treatment to Tune the Selectivity of CO2 Reduction toward Valuable Products

作者：Ma, Zhipeng; Tsounis, Constantine; Toe, Cui Ying; Kumar, Priyank, V; Subhash, Bijil; Xi, Shibo; Yang, Hui Ying; Zhou, Shujie; Lin, Zeheng; Wu, Kuang-Hsu; Wong, Roong Jien; Thomsen, Lars; Bedford, Nicholas M.; Lu, Xunyu; Ng, Yun Hau; Han, Zhaojun^*; Amal, Rose^*

来源：ACS Catalysis, 2022, 12(9): 4792-4805.

DOI：10.1021/acscatal.1c05431

• electrochemical treatment
• Cu nanoparticles
• vertical graphene
• surface reconstruction
• selective CO2RR

Reconstructing a catalyst with tunable properties is essential for achieving selective electrochemical CO2 reduction reaction (CO2RR). Here, a reduction-oxidation-reduction (ROR) electrochemical treatment is devised to advisedly reconstruct copper nanoparticles on vertical graphene. Undercoordinated sites and oxygen vacancies constructed on the Cu active sites during the ROR treatment enhance the CO2RR activity. Moreover, by varying the oxidation potential while maintaining the reduction potential during the ROR treatment, CO2RR selectivity can be tuned between *COOH- and *OCHO-derived products. Specifically, rich grain boundaries are formed on the ROR catalyst with a high oxidation potential (+1.2 VRHE), favoring the *COOHOCCO adsorption and leading C-C coupling to *COOH-derived products, while the catalyst undergoing ROR at a low oxidation potential (+0.8 VRHE) lacks grain boundaries, resulting in highly selective formate (*OCHO-derived) production. Our findings are evidenced by combined in situ and ex situ characterizations and theoretical calculations.

• 单位
  测试单位; 南阳理工学院