Electrochimica Acta, Vol.296, 259-267, 2019
Boosting oxygen evolution by surface nitrogen doping and oxygen vacancies in hierarchical NiCo/NiCoP hybrid nanocomposite
Oxygen evolution reaction has attracted enormous interest due to sluggish kinetics in water splitting reaction. In recent years, Co and Ni-based materials have been explored as excellent choices in highly efficient and affordable noble metal-free catalysts. Herein, a heterostructure of NiCo alloy and phosphide (NiCo/NiCoP) hybrid is prepared by using hydrothermal and calcination method. This hybrid catalyst manifests outstanding OER electrocatalytic performance, as demonstrated by an ultralow Tafel slope of 55 mV dec(-1), low overpotential of 290 mV at 10 mA cm(-2), and long-term chemical stability. Benefiting from the incorporation of nitrogen atom, surface oxygen vacancies, and synergistic coupling effect between alloy and phosphide, the hybrid catalyst can expose more accessible active sites and facilitate the release of oxygen bubbles. Our findings demonstrated that this bimetallic alloy/phosphide hybrid can serve as an efficient and durable electrocatalyst for the oxygen evolution reaction. (C) 2018 Elsevier Ltd. All rights reserved.