Wearable supercapacitors on polyethylene terephthalate fabrics with good wash fastness and high flexibility

Abstract

All solid-state micro-supercapacitors (MSC) have emerged as attractive energy-storage units for portable and wearable electronics. Here, we describe a textile-based solid-state MSC via laser scribing of graphene oxide (GO) coatings on a flexible polyethylene terephthalate (PET) fabric. The laser-scribed graphene oxide layers (LGO) possess three-dimensionally porous structure suitable for electrochemical-double-layer formation. To improve the wash fastness and the flexibility of the as-prepared MSCs, glutaraldehyde (GA) was employed to crosslink the GO layers and PVA-gel electrolyte onto the PET fabric. The resultant all solid-state MSCs exhibited excellent flexibility, high areal specific capacitance (756 μF·cm−2 at 20 mV·s−1), and good rate capability when subject to bending and laundering. Furthermore, the MSC device showed a high power density of about 1.4 W·cm−3 and an energy density of 5.3 × 10−5 Wh·cm−3, and retained 98.3% of its initial capacitance after 1000 cycles at a current density of 0.5 mA·cm−2. This work is the first demonstration of in-plane MSCs on PET fabric surfaces with enhanced durability and flexibility.