Effect of heat-treating temperatures on electrochemical behaviors of Ni-B alloys in an alkaline solution

To evaluate the effect of heat-treating temperatures on electrochemical behaviors of Ni-B alloys in an alkaline solution, amorphous Ni-B alloy was prepared via a chemical reduction method, and Ni-B alloys with different crystallizations were synthesized by heating the amorphous alloy at 300-700°C. The crystal structures and the electrochemical behaviors of the Ni-B alloys were characterized by X-ray diffraction (XRD) and cyclic voltammetry (CV), respectively. It is found that increasing heat-treating temperatures, the Ni-B alloys change from amorphous phase to crystal phases, and the existence of B volatilization become notable. The polarizations increase with fast scanning rate, and the potentials of the H₂-release reactions of Ni-B alloys and H₂O overlap partially with each other. The result indicates that Ni-B alloys have good electrochemical performances in a 6 mol/L KOH alkaline solution.