Enhanced Electrochemical Performance of NiO Nanoflakes Assembled on ZnCl2-Activated Carbonized Filter Paper

A composite formed of NiO nanoflakes assembled on carbonized filter paper (CFP) has been successfully synthesized by a hydrothermal route with subsequent annealing. The CFP substrate presented a three-dimensional (3D) network structure. The composite electrode demonstrated high capacity and good cyclic and rate capabilities. It delivered a capacity of 724 mA h g(-1) at current density of 100 mA g(-1) after 100 cycles without apparent capacity fading during cycling. It delivered a capacity of 446 mA h g(-1) even at high current density of 1000 mA g(-1). The composite achieves better battery performance through ZnCl2 activation compared with conventional HNO3 activation.