Guan Daqin, Zhou Jing, Huang Yu-Cheng, Dong Chung-Li, Wang Jian-Qiang, Zhou Wei, Shao Zongping
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 211800, China.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201204, China.
Nat Commun. 2019 Aug 21;10(1):3755. doi: 10.1038/s41467-019-11847-w.
Facile and reliable screening of cost-effective, high-performance and scalable electrocatalysts is key for energy conversion technologies such as water splitting. ABO perovskites, with rich constitutions and structures, have never been designed via activity descriptors for critical hydrogen evolution reaction (HER). Here, we apply coordination rationales to introduce A-site ionic electronegativity (AIE) as an efficient unifying descriptor to predict the HER activities of 13 cobalt-based perovskites. Compared with A-site structural or thermodynamic parameter, AIE endows the HER activity with the best volcano trend. (GdLa)BaCoO predicted from an AIE value of 2.33 exceeds the state-of-the-art Pt/C catalyst in electrode activity and stability. X-ray absorption and computational studies reveal that the peak HER activities at a moderate AIE value of ~2.33 can be associated with the optimal electronic states of active B-sites via inductive effect in perovskite structure (200 nm depth), including Co valence, Co-O bond covalency, band gap and O 2p-band position.
简便且可靠地筛选具有成本效益、高性能且可扩展的电催化剂是诸如水分解等能量转换技术的关键。具有丰富组成和结构的ABO钙钛矿，从未通过用于关键析氢反应（HER）的活性描述符进行设计。在此，我们应用配位原理引入A位离子电负性（AIE）作为一种有效的统一描述符，以预测13种钴基钙钛矿的HER活性。与A位结构或热力学参数相比，AIE赋予HER活性最佳的火山趋势。根据约2.33的AIE值预测的（GdLa）BaCoO在电极活性和稳定性方面超过了目前最先进的Pt/C催化剂。X射线吸收和计算研究表明，在约2.33的适度AIE值处的峰值HER活性可通过钙钛矿结构（约200nm深度）中的诱导效应与活性B位的最佳电子态相关联，包括Co价态、Co-O键共价性、带隙和O 2p带位置。
