Carbon dot-modified mesoporous carbon as a supercapacitor with enhanced light-assisted capacitance

Abstract

A light-charging energy storage device is a promising approach of utilizing solar energy, and the reasonable design of light-assisted supercapacitors with photosensitive materials is one of the efficient ways to realize solar energy conversion and storage. Here, the electrode material (OPC-CDs-700) prepared by combining procanthocyanins with carbon dots (CDs) can reach the specific capacitance of 312 F g⁻¹ at 0.1 A g⁻¹ under visible light, which is an increase of 54.4% compared with that of under dark conditions. Besides, this light-assisted supercapacitor exhibits excellent cyclic stability after 4000 cycles. A series of electrochemical measurements show that CDs could stabilize the charge under light illumination due to its photoactivity, thus increasing the accumulation and storage of charge on the surface of OPC-CDs-700. This study provides new prospects for the progress of photosensitive energy devices and application of solar energy.