Vertical finger-like asymmetric supercapacitors for enhanced performance at high mass loading and inner integrated photodetecting systems

Abstract

Herein, a vertical finger-like asymmetric supercapacitor (VFASC) comprising a reduced graphene oxide–manganese dioxide–polypyrrole (RGO–MnO₂–PPy) positive electrode and reduced graphene oxide–molybdenum trioxide (RGO–MoO₃) negative electrode was fabricated for the first time. The relationship between specific capacitance and mass loading of the VFASC was systematically studied. To our surprise, contrary to the general problem faced by supercapacitors, the specific capacitance of VFASC increased with an increase in the mass loading of the electrode. Furthermore, as the VFASC supplied a potential and MoO₃ guaranteed photodetection capacity, the VFASC also acted as a photodetector with excellent sensitivity for the detection of white light without the use of additional external connected systems. This study presents an essential strategy for the preparation of high performance supercapacitors with high mass loading, low production cost, energy efficiency, space saving and simple integrated photodetection systems.