Effect of synthesis method on the structure and electrochemical behaviour of Co–Si particles

Co–Si particles were prepared by means of three methods as sample A, B, and C. Structures of the samples were characterized by XRD and the electrochemical hydrogen storage properties were studied as negative electrodes in aqueous KOH solution. Results of cyclic voltammetry (CV) and cycling stability demonstrated that samples A and B showed excellent electrochemical reversibility and relatively high discharge capacities, whose maximum capacity are 245 and 214 mAh/g and kept 207.7 and 189.5 mAh/g after 80 cycles at current density 50 mAh/g. By comparing the XRD patterns of the electrodes on different charge–discharge states, the discharge capacity was attributed to hydrogenation of Co–Si particles.