Enhancement of dye-sensitized solar cells using Zr/N-doped TiO₂ composites as photoelectrodes

In this study, the effect of Zr doping on the performance of dye-sensitized solar cells (DSSCs) based on Zr/N-doped TiO₂ photoelectrodes was investigated. Zr/N-doped TiO₂ nanoparticles were synthesized with various Zr doping contents using the sol-gel method. The Zr/N-doped TiO ₂ nanoparticles had high surface areas, uniform particle sizes, and a strong red shift of their absorption into the visible region as compared with P25 nanoparticles. DSSCs fabricated with a 0.01 M Zr/N-doped TiO₂ photoelectrode achieved a maximum power conversion efficiency of 12.62% with a short-circuit current (J_sc) of 26.37 mA cm^-2, open-circuit voltage (V_oc) of 738 mV, and fill factor (FF) of 67.3% after TiCl₄ treatment. The increased energy conversion efficiency was attributed to the higher dye loading, reduced charge recombination, and enhanced charge transport.