CoP/EEBP/N-FLGS Nanocomposite as an Efficient Electrocatalyst of Hydrogen Evolution Reaction in Alkaline Media

Abstract

The search for new hydrogen evolution reaction (HER) electrocatalysts with lower cost and higher activity and stability than noble metal catalysts is essential. In this regard cobalt phosphide is considered one of the most promising nanomaterials. The present work proposes a simple and efficient method for the synthesis of a nanocomposite of graphene–phosphorene structures decorated with CoP nanoparticles 2–5 nm in size via the electrochemical exfoliation of black phosphorus carried out in the presence of nitrogen-doped few-layer graphene structures and followed by solvothermal synthesis in a Co2+-containing solution. The obtained CoP/EEBP/N-FLGS nanocomposite demonstrates high electrocatalytic activity and stability towards HER in an alkaline medium. The nanocomposite is characterized by an overpotential of 190 mV at a current density of 10 mA cm−2 as well as a small Tafel slope (78 mV dec−1). These characteristics make the CoP/EEBP/N-FLGS nanocomposite superior to most electrocatalysts based on cobalt phosphides. The results of this study could be in demand for the future design and improvement of HER electrocatalysts.

Keywords

• phosphorene
• few-layer graphene structures
• cobalt phosphides
• nanocomposites
• electrochemical exfoliation of graphite
• hydrogen evolution reaction