Facile synthesis of V-doped CoP nanoparticles as bifunctional electrocatalyst for efficient water splitting

Adjusting the intrinsic activity and conductivity of electrocatalysts may be a crucial way for excellent performance for water splitting. Herein, the rational design of vanadium element doped cobalt phosphide（V-doped Co P） nanoparticles has been investigated through a facile gaseous phosphorization using cobalt vanadium oxide or hydroxide(Co-V hydr（oxy）oxide) as precursor. The physical characterization shows that the homogeneous dispersion of V element on V-doped Co P nanoparticles have obtained, which may imply the enhanced electrocatalytic activity for hydrogen evolution reaction（HER） and oxygen evolution reaction（OER）. The electrochemical measurements of the prepared V-doped Co P in alkaline electrolyte demonstrate the superior electrocatalytic activity for both HER(overpotential of 235 m V@10 m A cm;)and OER(overpotential of 340 m V @10 m A cm;). Further, V-doped Co P nanoparticles used as anode and cathode simultaneously in a cell require only 370 m V to achieve a current density of 10 m A cm;. The outstanding electrocatalytic activity may be ascribed to the improved conductivity and intrinsic activity owing to phosphating and the doping of V element. In addition, the long-term stability of V-doped Co P has been obtained. Therefore, metal doping into transition metal-based phosphides may be a promising strategy for the remarkable bifunctional electrocatalyst for water splitting.