Chen Mingfa, Chang Kuan, Zhang Yu, Zhang Zhenbao, Dong Yuming, Qiu Xiaoyu, Jiang Heqing, Zhu Yongfa, Zhu Jiawei
Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, 214122, Wuxi, China.
Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101, Qingdao, China.
Angew Chem Int Ed Engl. 2023 Oct 26;62(44):e202305530. doi: 10.1002/anie.202305530. Epub 2023 Aug 9.
Despite the intriguing potential shown by Sn-based perovskite oxides in CO electroreduction (CO RR), the rational optimization of their CO RR properties is still lacking. Here we report an effective strategy to promote CO -to-HCOOH conversion of Sn-based perovskite oxides by A-site-radius-controlled Sn-O bond lengths. For the proof-of-concept examples of Ba Sr SnO , as the A-site cation average radii decrease from 1.61 to 1.44 Å, their Sn-O bonds are precisely shortened from 2.06 to 2.02 Å. Our CO RR measurements show that the activity and selectivity of these samples for HCOOH production exhibit volcano-type trends with the Sn-O bond lengths. Among these samples, the Ba Sr SnO features the optimal activity (753.6 mA ⋅ cm ) and selectivity (90.9 %) for HCOOH, better than those of the reported Sn-based oxides. Such optimized CO RR properties could be attributed to favorable merits conferred by the precisely controlled Sn-O bond lengths, e.g., the regulated band center, modulated adsorption/activation of intermediates, and reduced energy barrier for *OCHO formation. This work brings a new avenue for rational design of advanced Sn-based perovskite oxides toward CO RR.
尽管锡基钙钛矿氧化物在CO电还原（CO RR）中展现出了引人关注的潜力，但其CO RR性能的合理优化仍有所欠缺。在此，我们报道了一种通过A位半径控制Sn - O键长来促进锡基钙钛矿氧化物将CO转化为HCOOH的有效策略。以BaSrSnO为例进行概念验证，随着A位阳离子平均半径从1.61 Å减小到1.44 Å，其Sn - O键从2.06 Å精确缩短至2.02 Å。我们的CO RR测量结果表明，这些样品对HCOOH生成的活性和选择性随Sn - O键长呈现出火山型趋势。在这些样品中，BaSrSnO对HCOOH具有最佳活性（753.6 mA·cm²）和选择性（90.9%），优于已报道的锡基氧化物。这种优化的CO RR性能可归因于精确控制的Sn - O键长赋予的有利特性，例如能带中心的调控、中间体吸附/活化的调节以及*OCHO形成的能垒降低。这项工作为合理设计用于CO RR的先进锡基钙钛矿氧化物开辟了一条新途径。
