Preparation of Co/Ni nanoparticles doped g-C3N4 for improving the electrochemical hydrogen storage performance of Co0.9Cu0.1Si alloy

Abstract

A facile liquid-phase reduction strategy was used to prepare cobalt and nickel nanoparticles doped graphitic carbon nitride (g-C3N4). Co0.9Cu0.1Si alloy was manufactured by mechanical alloying. Subsequently, a series of g-C3N4, Co-g-C3N4 and Ni-g-C3N4 modified Co0.9Cu0.1Si composites were fabricated via ball milling. The electrochemical hydrogen storage behaviors of metal doped g-C3N4/Co0.9Cu0.1Si composite electrodes were studied for the first time. Ultimately, Co0.9Cu0.1Si + Co-g-C3N4 and Co0.9Cu0.1Si + Ni-g-C3N4 revealed preferable discharge capacity of 575.8 mA h/g and 561.0 mA h/g than Co0.9Cu0.1Si + g-C3N4 and conventional Co0.9Cu0.1Si electrodes. The g-C3N4 offered more electrochemical active sites and beneficial interface for charge transfer. The metal particles within g-C3N4 further improved the electrocatalytic activity. The metal nanoparticles and g-C3N4 played synergistic effect in enhancing the hydrogen diffusion and electrochemical behavior of Co0.9Cu0.1Si alloy. Moreover, Co-g-C3N4 and Ni-g-C3N4 modified Co0.9Cu0.1Si also demonstrated better capacity retention, high-rate dischargeability (HRD) and kinetics properties. Accordingly, Co/Ni nanoparticles doped g-C3N4 can be considered as effective material for hydrogen storage alloy modification.