Co‐Sensitization Effect of CNQDs and Anthocyanin on TiO₂ for High‐Efficiency Dye‐Sensitized Solar Cells: Experimental and Theoretical Insights

This study investigates the fabrication and characterization of natural pigment and carbon nitride quantum dots (CNQDs) co‐sensitized solar cells. The results showed that CNQDs@TiO 2 significantly improved light absorption and charge transfer properties. The effects of pH and temperature were examined to assess their influence on DSSC performance. It was found that an acidic medium yields the best results, with an optimal temperature of 25 °C. Photovoltaic measurements revealed a significant efficiency improvement in DSSCs, increasing from 2.7% for anthocyanin@TiO 2 to 8.6% when modified with anthocyanine & CNQDs@TiO 2 . In addition, the fill factor was improved from 0.46 to 0.63, respectively. The structural composition, size, morphology, and optical properties of CNQDs@TiO 2 were characterized using FTIR, DRS, XRD, FESEM, EDX, and TEM analytical techniques. DFT calculations were employed to learn more about the mechanism, efficiency, and photovoltaic properties of synthesized DSSCs. The theoretical results agree with experimental data in which the anthocyanine & CNQDs @ TiO 2 system is more efficient. CNQDs can be mediators, broadening the spectrum of light harvesting and providing extra bands that facilitate electron transitions.