Bifunctionality and Mechanism of Electrodeposited Nickel–Phosphorous Films for Efficient Overall Water Splitting. Issue 1 (4th December 2015) - Jiang, Nan
Abstract: Efficient, stable, and low‐cost electrocatalysts are crucial for realizing large‐scale water splitting. Herein, we report that electrodeposited nickel–phosphorous (Ni–P) films can act as efficient bifunctional electrocatalysts for overall water splitting. The as‐prepared Ni–P films exhibit remarkable catalytic performance for both H2 and O2 evolution reactions (HER and OER) in alkaline media, achieving a current density of 10 mA cm −2 at overpotentials of −93 mV for HER and 344 mV for OER with Tafel slopes of 43 and 49 mV dec −1, respectively, rivaling the performance of Pt and IrO2 . Various techniques were employed to probe the composition and morphology of the Ni–P films prior to and post catalysis, revealing the major composition of the as‐prepared and post‐HER films as metallic nickel and nickel phosphide, which partially transform to nickel oxides during OER. It was also found that the catalytic rate of OER catalyzed by Ni–P was first order in the activity of the hydroxide anion. Abstract : Overall water splitting : Electrodeposited nickel–phosphorous films (Ni–P) function as efficient bifunctional catalysts for overall water splitting under strong alkaline conditions, rivalling the performance of the state‐of‐the‐art catalysts, Pt and IrO2 .