Polyluminol-polyoxometalate hybrid hydrogels as flexible and soft supercapacitor electrodes

Abstract

The present study describes the preparation of novel polyacrylamide (PAM)/sodium alginate (SA)-polyluminol (PLum)/polyoxometalate (Pom) hybrid hydrogels and their application as electrodes in supercapacitors. The successful incorporation of PLum and Pom into the hybrid hydrogel was confirmed by FTIR. The chemical composition of the hybrid hydrogel was identified using X-ray photoelectron spectroscopy (XPS). The hybrid hydrogel is soft and possesses good mechanical stability under various forms of deformation. Galvanostatic charge–discharge (GCD) and cyclic voltammetry (CV) measurements showed that by combining the pseudocapacitance of PLum with the reversible redox activity of Pom, enhanced electrochemical performance is obtained. As a proof-of-concept, a flexible supercapacitor device was fabricated which exhibited a specific capacitance of 134.6 mF cm⁻² and 87.9% retention of the initial capacitance after 1000 cycles. These hybrid hydrogels are considered promising energy storage candidates for wearable and flexible electronics.