Fabrication and Characterization of Planar on-Chip Micro-Supercapacitors Based on Nitrogen and Oxygen Co-Doped Graphene Quantum Dots by Modified Liquid-Air Interface Self-Assembly Method

Abstract

Planar micro-supercapacitors stand out among micro/nano energy storage components for their high power, high energy, long life and fast time response. In this paper, all-solid-state planar on-chip micro-supercapacitors with high power characteristics were prepared by modified liquid-air interface self-assembly method, photolithography and sputtering gold. The nitrogen and oxygen co-doped graphene quantum dots electrode films are continuous and uniform, and the surface contains a large number of nitrogen and oxygen chemical bonds and functional groups. The finger width of the supercapacitors is 50 μm, the gap width is 50 μm and a number of electrode fingers is 100. In terms of performance, the supercapacitors had a very short time constant (2.16 μs), high power density (15.80 μW cm−2) and excellent cycle stability (94.5% capacity retention after 10000 cycles).