All-in- One Graphene-Based Composite Fiber Supercapacitor

Abstract

Graphene fibers (GF) have attracted great interest in wearable electronics applications due to their excellent mechanical flexibility and superior electrical conductivity. Herein, a graphene/MnO 2 composite hybrid supercapacitor fiber device has been devised. The unique design of this device overcomes the inconvenience and short circuit risk of conventional designs. The backbone of the device consists of GF that not only provides a durable scaffold for the entire device, but also ensures fast electron transfer during charge-discharge. The introduction of a MnO 2 film with abundant active sites enhanced the pseudocapacitance dramatically, compared to pristine GF. The entire device exhibits outstanding mechanical strength as well as good electrocapacitive performance with a volumetric capacitance of 29.6 F cm-3 at 2 mv s-1 . The capacitance of the device didn’t fade at all under bending testing from 0° to 150°, while the capacitance retention was kept 93% after 1000 cycles. These unique features make this device a promising candidate for applications in wearable fabric supercapacitors.