Feng Jinxian, Liu Chunfa, Qiao Lulu, An Keyu, Lin Sen, Ip Weng Fai, Pan Hui
Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR, 999078, China.
State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350108, China.
Adv Sci (Weinh). 2024 Oct;11(39):e2407019. doi: 10.1002/advs.202407019. Epub 2024 Aug 19.
Electrolyte plays crucial roles in electrochemical CO reduction reaction (e-CORR), yet how it affects the e-CORR performance still being unclarified. In this work, it is reported that Sn-Zn hybrid oxide enables excellent CO-to-HCOO conversion in KHCO with a HCOO Faraday efficiency ≈89%, a yield rate ≈0.58 mmol cm h and a stability up to ≈60 h at -0.93 V, which are higher than those in NaHCO and KSO. Systematical characterizations unveil that the surface reconstruction on Sn-Zn greatly depends on the electrolyte using: the Sn-SnO/ZnO, the ZnO encapsulated Sn-SnO/ZnO and the Sn-SnO/Zn-ZnO are reconstructed on the surface by KHCO, NaHCO and KSO, respectively. The improved CO-to-HCOO performance in KHCO is highly attributed to the reconstructed Sn-SnO/ZnO, which can enhance the charge transportation, promote the CO adsorption and optimize the adsorption configuration, accumulate the protons by enhancing water adsorption/cleavage and limit the hydrogen evolution. The findings may provide insightful understanding on the relationship between electrolyte and surface reconstruction in e-CORR and guide the design of novel electrocatalyst for effective CO reduction.
电解质在电化学CO还原反应（e-CORR）中起着至关重要的作用，但其如何影响e-CORR性能仍不清楚。在这项工作中，据报道，Sn-Zn混合氧化物在KHCO中能实现优异的CO到HCOO的转化，HCOO法拉第效率约为89%，产率约为0.58 mmol cm⁻² h⁻¹，在-0.93 V下稳定性高达约60 h，这些性能高于在NaHCO和K₂SO₄中的性能。系统表征表明，Sn-Zn上的表面重构很大程度上取决于所使用的电解质：Sn-SnO/ZnO、ZnO包覆的Sn-SnO/ZnO和Sn-SnO/Zn-ZnO分别在KHCO、NaHCO和K₂SO₄作用下在表面发生重构。KHCO中CO到HCOO性能的提升高度归因于重构后的Sn-SnO/ZnO，它可以增强电荷传输，促进CO吸附并优化吸附构型，通过增强水的吸附/裂解来积累质子，并限制析氢。这些发现可能为深入理解e-CORR中电解质与表面重构之间的关系提供见解，并指导设计用于有效CO还原的新型电催化剂。
