Selenium doped nickel nanosheet array for oxygen evolution reaction

Developing an oxygen evolution reaction electrocatalyst with low cost, abundant reserves and excellent performance is essential for the large scale application of renewable hydrogen energy. Herein, a selenium doped hierarchical Ni-based electrocatalyst was fabricated. Nickel nanosheet array (NNA) was firstly electrodeposited on stainless steel, and then selenium was doped in the NNA to form a hierarchical nanosheet structure via a hydrothermal process. The effect of hydrothermal temperature and duration on the OER performance were investigated. Results shown that after selenization at 140 °C for 12 h, the NNA electrodeposited for 30 min performed best OER performance with a current density of 50 mA cm−2 at overpotential of 365 mV and a small Tafel slope of about 34 mV dec−1. This work provides a valuable strategy to design high efficiency electrocatalysts and shows the universality of selenization for improving catalytic performance.