Evaluation of a V8C7 Anode for Oxygen Evolution in Alkaline Media: Unusual Morphological Behavior

被引：11

作者：

Kawashima, Kenta ^{[1
]}

Cao, Chi L. ^{[2
]}

Li, Hao ^{[1
,3
]}

Marquez-Montes, Raul A. ^{[1
]}

Wygant, Bryan R. ^{[1
]}

Son, Yoon Jun ^{[2
]}

Guerrera, Joseph, V ^{[1
]}

Henkelman, Graeme ^{[1
,3
]}

Mullins, C. Buddie ^{[4
,5
]}

机构：

[1] Univ Texas Austin, Dept Chem, Austin, TX 78712 USA

[2] Univ Texas Austin, John J McKetta Dept Chem Engn, Austin, TX 78712 USA

[3] Univ Texas Austin, Oden Inst Computat Engn & Sci, Austin, TX 78712 USA

[4] Univ Texas Austin, John J McKetta Dept Chem Engn, Dept Chem, Austin, TX 78712 USA

[5] Univ Texas Austin, Ctr Electrochem, Austin, TX 78712 USA

来源：

ACS SUSTAINABLE CHEMISTRY & ENGINEERING | 2020年 / 8卷 / 37期

基金：

美国国家科学基金会;

关键词：

precatalyst; electrocatalyst; oxygen evolution reaction (OER); vanadium carbide; water splitting; MOLYBDENUM CARBIDE NANOPARTICLES; BIFUNCTIONAL ELECTROCATALYST; DOPED CARBON; HYDROGEN; COBALT; PERFORMANCE; TRANSITION; EFFICIENT; PHOSPHIDES; REDUCTION;

D O I：

10.1021/acssuschemeng.0c04759

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Metallic vanadium carbide (V8C7) with cubic symmetry is examined as an oxygen evolution reaction (OER) precatalyst in alkaline media. Herein, we used quasi in situ scanning electron microscopy and energy-dispersive X-ray spectrometry to investigate the structural transformation of the precatalyst V8C7 microparticles during extended cyclic voltammetric (CV) OER testing. Interestingly, an anisotropic morphological transformation (from a distorted sphere to a cuboid) of V8C7 was observed. Our theoretical and experimental results strongly suggest that this morphological change happens due to the selective self-oxidation and dissolution of the V8C7(110) and (111) surfaces and the subsequent exposure of the relatively stable (100), (010), and (001) surfaces. These results also suggest that these stable facets are preferable for the OER, and a current density of 10 mA.cm(-2) was delivered at an overpotential of 503 mV after the extended CV OER testing.

引用

页码：14101 / 14108

页数：8

共 52 条

[1] Bamboo-Structured Nitrogen-Doped Carbon Nanotube Coencapsulating Cobalt and Molybdenum Carbide Nanoparticles: An Efficient Bifunctional Electrocatalyst for Overall Water Splitting [J].