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 CoP)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 CoP 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 CoP in alkaline electrolyte demonstrate the superior electrocatalytic activity for both HER(overpotential of 235 mV@10 mA cm^-2)and OER(overpotential of 340 mV@10 mA cm^-2).Further,V-doped CoP nanoparticles used as anode and cathode simultaneously in a cell require only 370 mV to achieve a current density of 10 mA cm^-2.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.