Stability, reusability, and equivalent circuit of TiO2/treated metakaolinite-based dye-sensitized solar cell: effect of illumination intensity on Voc and Isc values

In this research, treated metakaolinite (TMK) was introduced into the TiO₂ photoelectrode to fabricated dye-sensitized solar cells (DSSCs). The photovoltaic cells have four main natural components, i.e., a photosensitizer (carotenoid bixin), photoelectrode (TiO₂/kaolinite), electrolyte (glycerine carbonate derivative), and counter-electrode (carbon). Their stability, reusability, and equivalent circuit were studied. The presence of 5% of TMK in anatase TiO₂ paste decreased the TiO₂ band gap from 3.21 to 3.16?eV. The result showed that the presence of 5% of TMK in TiO₂ paste was more favorable to obtain higher energy conversion efficiency. Under a light intensity of 200?W/m², it produced an energy conversion yield of 0.086%. The combination of the electrolyte and the TMK demonstrated a synergistic effect to improve the electrical properties of the DSSC. The energy storage function worked well until the third day of analysis. The DSSC based on TiO₂/TMK photoelectrode exhibited 16 times better stability than pure TiO₂-based photoelectrode. The Faraday charge transfer processes showed that the TiO₂/TMK photoelectrode is not in direct contact with the carbon counter-electrode.