当前位置：
X-MOL 学术
›
J. Am. Chem. Soc.
›
论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Identification of the Active-Layer Structures for Acidic Oxygen Evolution from 9R-BaIrO3 Electrocatalyst with Enhanced Iridium Mass Activity
Journal of the American Chemical Society ( IF 15.0 ) Pub Date : 2021-10-25 , DOI: 10.1021/jacs.1c04087 Na Li 1 , Liang Cai 1, 2 , Chao Wang 1 , Yue Lin 3 , Jinzhen Huang 2, 4 , Hongyuan Sheng 2 , Haibin Pan 1 , Wei Zhang 1 , Qianqian Ji 1 , Hengli Duan 1 , Wei Hu 1 , Wenhua Zhang 1 , Fengchun Hu 1 , Hao Tan 1 , Zhihu Sun 1 , Bo Song 4 , Song Jin 2 , Wensheng Yan 1
Journal of the American Chemical Society ( IF 15.0 ) Pub Date : 2021-10-25 , DOI: 10.1021/jacs.1c04087 Na Li 1 , Liang Cai 1, 2 , Chao Wang 1 , Yue Lin 3 , Jinzhen Huang 2, 4 , Hongyuan Sheng 2 , Haibin Pan 1 , Wei Zhang 1 , Qianqian Ji 1 , Hengli Duan 1 , Wei Hu 1 , Wenhua Zhang 1 , Fengchun Hu 1 , Hao Tan 1 , Zhihu Sun 1 , Bo Song 4 , Song Jin 2 , Wensheng Yan 1
Affiliation
|
Iridium-based perovskites show promising catalytic activity for oxygen evolution reaction (OER) in acid media, but the iridium mass activity remains low and the active-layer structures have not been identified. Here, we report highly active 1 nm IrOx particles anchored on 9R-BaIrO3 (IrOx/9R-BaIrO3) that are directly synthesized by solution calcination followed by strong acid treatment for the first time. The developed IrOx/9R-BaIrO3 catalyst delivers a high iridium mass activity (168 A gIr–1), about 16 times higher than that of the benchmark acidic OER electrocatalyst IrO2 (10 A gIr–1), and only requires a low overpotential of 230 mV to reach a catalytic current density of 10 mA cm–2geo. Careful scanning transmission electron microscopy, synchrotron radiation-based X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy analyses reveal that, during the electrocatalytic process, the initial 1 nm IrOx nanoparticles/9R-BaIrO3 evolve into amorphous Ir4+OxHy/IrO6 octahedrons and then to amorphous Ir5+Ox/IrO6 octahedrons on the surface. Such high relative content of amorphous Ir5+Ox species derived from trimers of face-sharing IrO6 octahedrons in 9R-BaIrO3 and the enhanced metallic conductivity of the Ir5+Ox/9R-BaIrO3 catalyst are responsible for the excellent acidic OER activity. Our results provide new insights into the surface active-layer structure evolution in perovskite electrocatalysts and demonstrate new approaches for engineering highly active acidic OER nanocatalysts.
更新日期：2021-11-03
京公网安备 11010802027423号