One-step synthesis and graphene-modification to achieve nickel phosphide nanoparticles with electrochemical properties suitable for supercapacitors

A facile one-step method has been developed to synthesize nickel phosphide (Ni2P) nanoparticles which were further modified by graphene to form graphene-modified Ni2P nanocomposites. All of the synthesized samples were characterized in detail and investigated the corresponding electrochemical properties. Results show that the supercapacitor electrodes based on graphene-modified Ni2P nanocomposites exhibit better electrochemical properties compared to free Ni2P nanoparticles. When the loaded amount of graphene is 5% (wt%), the nanocomposite electrodes show higher specific capacitance, obviously improved cycle stabilization, better rate capability and higher energy density. This enhanced electrochemical behavior results from the graphene-modified Ni2P nanocomposite network structure which not only promotes efficient charge transport and electrolyte diffusion, but also prevents the volume expansion/contraction and corrosion of Ni2P nanoparticles. These encouraging findings demonstrate the possibility of graphene-modified Ni2P nanocomposites for applications in high-performance supercapacitors.