State Key Lab of High Performance Ceramics and Superfine microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 201899, Shanghai, China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 100049, Beijing, China.
Nat Commun. 2023 Jan 17;14(1):280. doi: 10.1038/s41467-023-35783-y.
Self-reconstruction has been considered an efficient means to prepare efficient electrocatalysts in various energy transformation process for bond activation and breaking. However, developing nano-sized electrocatalysts through complete in-situ reconstruction with improved activity remains challenging. Herein, we report a bottom-up evolution route of electrochemically reducing CsRhI halide-perovskite clusters on N-doped carbon to prepare ultrafine Rh nanoparticles (~2.2 nm) with large lattice spacings and grain boundaries. Various in-situ and ex-situ characterizations including electrochemical quartz crystal microbalance experiments elucidate the Cs and I extraction and Rh reduction during the electrochemical reduction. These Rh nanoparticles from CsRhI clusters show significantly enhanced mass and area activity toward hydrogen evolution reaction in both alkaline and chlor-alkali electrolyte, superior to liquid-reduced Rh nanoparticles as well as bulk CsRhI-derived Rh via top-down electro-reduction transformation. Theoretical calculations demonstrate water activation could be boosted on CsRhI clusters-derived Rh nanoparticles enriched with multiply sites, thus smoothing alkaline hydrogen evolution.
自重构被认为是一种有效的方法，可以在各种能量转化过程中通过键的激活和断裂来制备高效的电催化剂。然而，通过完全原位重构来开发纳米级电催化剂以提高其活性仍然具有挑战性。在此，我们报告了一种自下而上的演化途径，即在 N 掺杂碳上电还原 CsRhI 卤化物钙钛矿簇以制备具有大晶格间距和晶界的超细 Rh 纳米颗粒（~2.2nm）。包括电化学石英晶体微天平实验在内的各种原位和异位表征阐明了电化学还原过程中 Cs 和 I 的提取以及 Rh 的还原。与液体还原的 Rh 纳米颗粒以及通过自上而下的电还原转化的块状 CsRhI 衍生的 Rh 相比，CsRhI 簇中的这些 Rh 纳米颗粒在碱性和氯碱电解质中对析氢反应表现出显著增强的质量和面积活性。理论计算表明，富含多活性位的 CsRhI 簇衍生 Rh 纳米颗粒可以促进水的活化，从而使碱性析氢过程更加平滑。
