Ye Ke, Zhou Zhiwen, Shao Jiaqi, Lin Long, Gao Dunfeng, Ta Na, Si Rui, Wang Guoxiong, Bao Xinhe
State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian, 116023, China.
Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Nantong Street 145, Harbin, 150001, China.
Angew Chem Int Ed Engl. 2020 Mar 16;59(12):4814-4821. doi: 10.1002/anie.201916538. Epub 2020 Feb 4.
The electrochemical CO reduction reaction (CO RR) to give C (formate and CO) products is one of the most techno-economically achievable strategies for alleviating CO emissions. Now, it is demonstrated that the SnO shell in Sn Cu catalyst with a hierarchical Sn-Cu core can be reconstructed in situ under cathodic potentials of CO RR. The resulting Sn Cu catalyst achieves a high current density of 406.7±14.4 mA cm with C Faradaic efficiency of 98.0±0.9 % at -0.70 V vs. RHE, and remains stable at 243.1±19.2 mA cm with a C Faradaic efficiency of 99.0±0.5 % for 40 h at -0.55 V vs. RHE. DFT calculations indicate that the reconstructed Sn/SnO interface facilitates formic acid production by optimizing binding of the reaction intermediate HCOO* while promotes Faradaic efficiency of C products by suppressing the competitive hydrogen evolution reaction, resulting in high Faradaic efficiency, current density, and stability of CO RR at low overpotentials.
通过电化学CO还原反应（CO RR）生成含碳（甲酸盐和CO）产物是缓解CO排放最具技术经济可行性的策略之一。现在有研究表明，具有分级Sn-Cu核的Sn Cu催化剂中的SnO壳层在CO RR的阴极电位下可原位重构。所得的Sn Cu催化剂在相对于可逆氢电极（RHE）为-0.70 V时实现了406.7±14.4 mA cm的高电流密度，碳法拉第效率为98.0±0.9%，并且在相对于RHE为-0.55 V时，以243.1±19.2 mA cm的电流密度和99.0±0.5%的碳法拉第效率保持稳定达40小时。密度泛函理论（DFT）计算表明，重构的Sn/SnO界面通过优化反应中间体HCOO*的吸附促进甲酸生成，同时通过抑制竞争性析氢反应提高含碳产物的法拉第效率，从而在低过电位下实现高法拉第效率、电流密度和CO RR稳定性。
