Colletotrichum gloeosporioides (endophytic fungi) mediated biosynthesis of TiO2 nanoparticles for high-performance dye-sensitized solar cell

This work reports an environmentally friendly protocol for synthesizing TiO2 nanoparticles (NPs) by utilizing endophytic fungi, Colletotrichum gloeosporioides (C. gloeosporioides). The fungi isolated from Thevetia peruviana, worked as a bio-capping agent to regulate the growing TiO2 NPs morphology and agglomeration behavior. The formation of TiO2 NPs was validated by surface plasmon resonance, observed using UV–vis spectroscopy. Using XRD and HRTEM, the structure, size, and shape of the as-synthesized anatase TiO2 NPs were characterized. BET analysis was used to examine the surface area and porosity. EIS revealed the greater charge collection efficiency and enhanced electron lifetime for the TiO2 obtained with N-3 (endophytic fungal extract). The dye-sensitized solar cell (DSSC) fabricated with bio-capped TiO2 (N-3) photoanode exhibited greater light-to-current conversion efficiency, 3.50 %; much enhanced compared to 0.98 % obtained with un-capped TiO2 NPs (N-1) based cell. The study demonstrated that the endophytic fungus C.gloeosporioides played a vital role in enhancing the cell performance.