Integrating Pt-free dye-sensitized solar cell and symmetric supercapacitor employing common electrode quaternary nanocomposite

Abstract

Energy demand is increasing day by day globally due to the increase of population in a drastic manner. Solar energy a renewable, abundant, eco-friendly energy is the best solution to meet the energy demand of the world. The dye-sensitized solar cells (DSSC) are the most reliable of the photovoltaics (PV) on account of their facile fabrication and pricing. Here a novel quaternary hybrid nanocomposite was substituted in the place of platinum (Pt) as a counter electrode and yielded exceptional results. The reduced graphene oxide/ manganese dioxide/ copper oxide/ cobalt oxide (rGO/MnO₂/CuO/Co₃O₄ (RMCC)) was prepared and employed as a counter electrode of the DSSC under varied photoanodes (PA) like as-synthesized titanium dioxide (TiO₂), zinc Oxide (ZnO) and titanium dioxide/zinc oxide TiO₂/ZnO with N-719 as dye medium, all coated over Fluorine doped tin oxide (FTO) glass as substrate. The DSSC constructed with RMCC as counter electrode (CE) was discovered to have a reliable photoconversion efficiency of 7.67 % which is 98.83 % of the Platinum substituted DSSC. The result was also testified by developing 60 such devices in total, under different photoanode material and was proved to be consistent, enabling the nanocomposite to develop into a positive example for CE in DSSC. Later this DSSC was integrated with a symmetric supercapacitor made of the same electrode material and gave a photovoltage of 0.828 V with areal-specific capacitance, energy and power density of 264.73 mF cm⁻², 25.208 μW h cm⁻² and 0.1656 mW cm⁻², respectively. The photo-supercapacitor device self-discharged at 548 s with an overall conversion efficiency of the photosupercapacitor is 8.98 % resulting in a self-charged energy device.