Flexible free-standing polyaniline/graphene/carbon nanotube plastic films with enhanced electrochemical activity for an all-solid-state flexible supercapacitor device

Abstract

A thin and ultralight PAN–graphene–MWCNTs–PPS plastic film with superior capacitive behavior was easily fabricated via homogeneous addition of polyethylene glycol (PEG) into a matrix consisting of a polyaniline–graphene–multi walled carbon nanotube–polyphenylene sulfide plastic composite. The PEG component can be selectively leached out from the composite by water at room temperature, which makes the PAN–graphene–MWCNTs–PPS plastic film display a network of open pores plus large surface area. The plastic film exhibited comprehensively excellent mechanical and electrochemical properties such as excellent flexibility, good mechanical strength, high wettability, low Ohmic resistance, a high areal capacitance of 582 mF cm⁻² at 1.6 mA cm⁻², and good rate capability with a capacity retention of 51.5% when the discharge current was amplified by more than 3 times. A flexible all-solid-state symmetric supercapacitor device assembled from two flexible plastic films exhibited superior mechanical stability, excellent electrochemical performance, a high operation voltage of 1.8 V and a long-term cycling life with 98% capacitance retention after 2000 cycles. This work opens up new opportunities to convert plastic waste to flexible energy storage devices for future portable and wearable electronics.