Electrochemical Hydrogen Storage Behaviors of Ultrafine Amorphous Co−B Alloy Particles

Abstract

Ultra-fine amorphous alloy particles (UAAP) of Co−B were synthesized and investigated as an anode material in aqueous KOH solution. The experimental results demonstrated that the Co−B particles so prepared show excellent electrochemical reversibility and considerably high charge−discharge capacity. The reversible discharge capacity of the Co−B UAAP electrode is found to exceed 300 mAh/g at a current rate 100 mA/g, similar to values for conventional hydrogen storage alloys. In addition, the cycling ability and high rate capability of the Co−B electrode are fairly good with only 10% capacity decay after 100 cycles at a high rate of 300 mA/g. These exceptional electrochemical performances are suggested to arise from the electrochemical hydrogen storage reaction on the Co−B material, which is brought about by the nanosize effects and special amorphous structure of the Co−B UAAP particles.