Photoresponsive MoS2 Se PPy electrodes for flexible supercapacitors with self charging capability under light

Photo-enhanced supercapacitors are a promising energy solution for next-generation applications. These devices integrate photosensitive materials into capacitive electrodes and enable both conversion and storage of solar energy in a single, compact system. In this study, we have developed a novel electrode that utilizes flexible indium tin oxide (ITO) substrates coated with a MoS2-Se-PPy film for use in flexible energy storage systems. The MoS2-Se-PPy photoelectrode showed an impressive specific capacity of 2.47 mAh/cm2 at a current density of 0.09 mA/cm2, with a remarkable increase to 3.95 mAh/cm2 under illumination, indicating a significant improvement in light-induced capacity. Using the prepared electrodes and a PVA-LiCl polymer electrolyte, symmetric and asymmetric photo-assisted supercapacitors with a two-electrode configuration were fabricated. A comparative analysis of their photoelectrochemical performance revealed that the asymmetric device exhibited higher capacity and energy density than the symmetric device. The results confirm that light irradiation increases the capacity of these devices, and they maintain their excellent capacity over longer periods. The results show that under illumination, both symmetric and asymmetric photo-assisted supercapacitors achieve specific capacities of 2.29 mAh/cm2 and 4.05 mAh/cm2 at a current density of 0.08 mA/cm2, which is an increase of 99% and 54%, respectively, compared to their performance under conventional electrical charging conditions. The fabricated devices also exhibit self-charging voltages of 0.84 V after 40 s of exposure for the symmetrical cells and 0.59 V after 40 s for the asymmetrical two-electrode cells. These results emphasize the effectiveness of these cells in using light to improve energy storage performance.