Wang Nan, Shao Chunfeng, Zhang Riguang, Zhang Yuan, Min Zhaojun, Chang Bing, Fan Maohong, Wang Jianji
Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, P. R. China.
State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, P. R. China.
Small. 2024 Mar;20(10):e2306129. doi: 10.1002/smll.202306129. Epub 2023 Oct 25.
Electrochemical CO reduction into high-value-added formic acid/formate is an attractive strategy to mitigate global warming and achieve energy sustainability. However, the adsorption energy of most catalysts for the key intermediate *OCHO is usually weak, and how to rationally optimize the adsorption of *OCHO is challenging. Here, an effective Bi-Sn bimetallic electrocatalyst (Bi -O-Sn @C) where a Bi-O-Sn bridge-type nanostructure is constructed with O as an electron bridge is reported. The electronic structure of Sn is precisely tuned by electron transfer from Bi to Sn through O bridge, resulting in the optimal adsorption energy of intermediate *OCHO on the surface of Sn and the enhanced activity for formate production. Thus, the Bi -O-Sn @C exhibits an excellent Faradaic efficiency (FE) of 97.7% at -1.1 V (vs RHE) for CO reduction to formate (HCOO ) and a high current density of 310 mA cm at -1.5 V, which is one of the best results catalyzed by Bi- and Sn-based catalysts reported previously. Impressively, the FE exceeds 93% at a wide potential range from -0.9 to -1.4 V. In-situ ATR-FTIR, in-situ Raman, and DFT calculations confirm the unique role of the bridge-type structure of Bi-O-Sn in highly efficient electrocatalytic reduction of CO into formate.
将电化学CO还原为高附加值的甲酸/甲酸盐是缓解全球变暖并实现能源可持续性的一种有吸引力的策略。然而，大多数用于关键中间体OCHO的催化剂的吸附能通常较弱，如何合理优化OCHO的吸附具有挑战性。在此，报道了一种有效的Bi-Sn双金属电催化剂（Bi -O-Sn @C），其中以O作为电子桥构建了Bi-O-Sn桥型纳米结构。通过电子从Bi经O桥转移到Sn，精确调节了Sn的电子结构，从而使中间体*OCHO在Sn表面具有最佳吸附能，并提高了甲酸盐生成活性。因此，Bi -O-Sn @C在-1.1 V（相对于可逆氢电极）下将CO还原为甲酸盐（HCOO ）时表现出97.7%的优异法拉第效率（FE），在-1.5 V时具有310 mA cm的高电流密度，这是先前报道的Bi基和Sn基催化剂催化的最佳结果之一。令人印象深刻的是，在-0.9至-1.4 V的宽电位范围内，FE超过93%。原位衰减全反射傅里叶变换红外光谱（ATR-FTIR）、原位拉曼光谱和密度泛函理论（DFT）计算证实了Bi-O-Sn桥型结构在高效电催化CO还原为甲酸盐中的独特作用。
