Carbon-MEMS-Based Alternating Stacked MoS2 @rGO-CNT Micro-Supercapacitor with High Capacitance and Energy Density

Abstract

A novel process to fabricate a carbon-microelectromechanical-system-based alternating stacked MoS₂ @rGO-carbon-nanotube (CNT) micro-supercapacitor (MSC) is reported. The MSC is fabricated by successively repeated spin-coating of MoS₂ @rGO/photoresist and CNT/photoresist composites twice, followed by photoetching, developing, and pyrolysis. MoS₂ @rGO and CNTs are embedded in the carbon microelectrodes, which cooperatively enhance the performance of the MSC. The fabricated MSC exhibits a high areal capacitance of 13.7 mF cm^-2 and an energy density of 1.9 µWh cm^-2 (5.6 mWh cm^-3 ), which exceed many reported carbon- and MoS₂ -based MSCs. The MSC also retains 68% of capacitance at a current density of 2 mA cm^-2 (5.9 A cm^-3 ) and an outstanding cycling performance (96.6% after 10 000 cycles, at a scan rate of 1 V s^-1 ). Compared with other MSCs, the MSC in this study is fabricated by a low-cost and facile process, and it achieves an excellent and stable electrochemical performance. This approach could be highly promising for applications in integration of micro/nanostructures into microdevices/systems.

Keywords: carbon; carbon nanotubes; micro-supercapacitors; microdevices; transition metal dichalcogenides.