Composites of Vanadium (III) Oxide (V₂O₃) Incorporating with Amorphous C as Pt-Free Counter Electrodes for Low-Cost and High-Performance Dye-Sensitized Solar Cells

To replace precious Pt-based counter electrodes (CEs) with a low-cost Pt-free catalyst of CEs is still a motivating hotspot to decrease the fabrication cost of dye-sensitized solar cells (DSSCs). Herein, four different V₂O₃@C composite catalysts were synthesized by pyrolysis of a precursor under N₂ flow at 1100 °C and further served as catalytic materials of CEs for the encapsulation of DSSCs. The precursors of V₂O₃@C composites have been prepared via a sol-gel method using different proportions of V₂O₅ with soluble starch in a H₂O₂ solution. Power conversion efficiencies (PCEs) of 3.59, 4.79, 5.15, and 5.06% were obtained from different V₂O₃@C composites, with soluble starch-to-V₂O₅ mass ratios (S/V) of 1:2, 1:1, 2:1, and 4:1, respectively, as CEs to reduce iodide/triiodide in DSSCs. The improvement of electrode performance is due to the combined effects on the increased specific surface area and the enhanced conductivity of V₂O₃@C composite catalysts.