Integration of VS₂ nanosheets into carbon for high energy density micro-supercapacitor

For portable electronics, the development of on-chip micro-supercapacitor (MSC) with high energy density is still a tremendous challenge. Carbon-based microelectrodes are very attractive for applications in MSCs, however, their potential window, porous structure and capacitance need to be enhanced and optimized. Herein, we report a pyrolyzed carbon/vanadium disulfide nanosheets (C/VS₂) microelectrode based MSC by modern micromachining photolithography and pyrolysis process. For this C/VS₂ composite microelectrode, carbon and VS₂ contribute synergistically with gel electrolyte and an improved volumetric capacitance with wide potential window is obtained. The fabricated MSC demonstrates a high specific volumetric capacitance of 86.4 F cm⁻³, a high energy and a power densities of 15.6 mWh·cm⁻³ and 2.88 W cm⁻³, respectively with an extended potential window (0–1.2 V). In addition, it shows an excellent cycling behavior, retaining 97.7% capacitance after 10,000 CV cycles at a scan rate of 500 mV s⁻¹. This proposed approach provides a highly promising strategy of fabricating high-performance energy storage devices for miniaturized electronics.