Laser-patterned PEDOT:PSS-aramid nanofiber composite electrodes for in-plane supercapacitors with high performance, shape-diversity and ultrahigh deformation resistance

The rapid development of portable and wearable modern electronics is in urgent need of the compatible energy storage devices, among which the flexible in-plane micro-supercapacitor (MSC) has emerged as a promising candidate. In this work, a facile and efficient laser-ablation technique was used to fabricate high performance metal-free all-solid-state in-plane MSCs with dimethyl sulfoxide-treated composite electrode (D-PA) composed of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS, PH1000) and aramid nanofibers. The effect of D-PA mass loading on the electrical and electrochemical properties of electrodes and devices was studied. The optimal MSC delivers high areal capacitance (15.4 mF/cm2 at 2 mV/s), superior charge/discharge cycling stability (capacitance hardly changes after 10,000 cycles), excellent rate performance (11.1 mF/cm2 at 3 mA/cm2) and ultrahigh resistance to arbitrary and extreme mechanical deformation (including circle-bending, free-twisting and multi-folding), which are superior to many state-of-the-art PH1000-based MSCs. Furthermore, performance of the shape-diverse device is easily tailored by series and/or parallel integration without usage of the metallic component. Such high performance MSC presents a great potential application in portable and wearable electronics even under severe deformed states.