Tracing the Effects of Nitrogen Doping and Sulfur Vacancy in Surging OER Electrocatalytic Activity of Bismuth Sulfide Nanorods

Abstract

Bismuth sulfide has become an attractive candidate in the electrocatalytic oxygen evolution reaction (OER), owing to its open coordination sites, unpaired electron orbitals, and mild electronegativity, but its OER performance is hindered by many deficiencies. The combination of heteroatom construction and vacancy engineering has been used to improve the OER performance of bismuth‐based electrocatalysts, but few studies can clearly describe the roles of dopants and vacancies in improving OER performance. Herein, N dopants and S vacancies in Bi2S3 nanorods via one‐step NH3/Ar plasma etching to investigate the enhanced OER performance are constructed. N dopants and S vacancies both regulated the intrinsic charge ordering of Bi2S3 nanorods, enhancing the p‐band center and Fermi level while also boosting the electroconductivity and wettability of the material. In addition, density functional theory calculations suggest that N doping promoted the adsorption of Bi sites, while S vacancies favored the desorption of S sites. Under the synergistic effects of N dopants and S vacancies, Bi2S3‐based electrocatalysts exhibited a low overpotential of 374 mV at 10 mA cm−2 and satisfactory durability, demonstrating a feasible strategy for exploiting main group element OER electrocatalysts.