Fig. 5From: Few-Layer Graphene Sheet-Passivated Porous Silicon Toward Excellent Electrochemical Double-Layer Supercapacitor ElectrodeCV curves of a as-etched and annealed PSi electrodes at a 25 mV/s scan rate. b Mesoporous, c hybrid-porous, and d macroporous PSi electrodes at 5–1000 mV/s scan rates, respectively. e Areal capacitance and f capacitive retention of annealed PSi electrodes with scan rates ranging from 5 to 1000 mV/sBack to article page