Mechanical ball-milling preparation of mass sandwich-like cobalt–graphene nanocomposites with high electrochemical hydrogen storage ability

Mass pure sandwich-like (hcp- and fcc-) Co/GE (graphene)/Co nanocomposites have been synthesized by direct ball-milling of Co and GE powders by adjusting the reaction conditions, and the maximum hydrogen storage capacity achieved was 899.5 mA h g−1 (3.29 wt% hydrogen).