Applied Surface Science, Vol.435, 1228-1236, 2018
All-solid-state flexible microsupercapacitors based on reduced graphene oxide/multi-walled carbon nanotube composite electrodes
All-solid-state flexible microsupercapacitors have been intensely investigated in order to meet the rapidly growing demands for portable microelectronic devices. Herein, we demonstrate a facile, readily scalable and cost-effective laser induction process for preparing reduced graphene oxide/multi-walled carbon nanotube composite, which can be used as the interdigital electrodes in microsupercapacitors. The obtained composite exhibits high volumetric capacitance about 49.35 F cm(-3), which is nearly 5 times higher than that of the pristine reduced graphene oxide film in aqueous 1.0 M H2SO4 solution (measured at a current density of 5 A cm(-3) in a three-electrode testing). Additionally, an all-solid-state flexible microsupercapacitor employing these composite electrodes with PVA/H3PO4 gel electrolyte delivers high volumetric energy density of 6.47 mWh cm(-3) at 10 mW cm(-3) under the current density of 20 mA cm(-3) as well as achieve excellent cycling stability retaining 88.6% of its initial value and outstanding coulombic efficiency after 10,000 cycles. Furthermore, the microsupercapacitors array connected in series/parallel can be easily adjusted to achieve the demands in practical applications. Therefore, this work brings a promising new candidate of prepare technologies for all-solid-state flexible microsupercapacitors as miniaturized power sources used in the portable and wearable electronics. (C) 2017 Elsevier B.V. All rights reserved.