Inverse Opal Photoelectrode Of Nb-Doped Tio2 Nanoparticles For Dye-Sensitized Solar Cell

In this study, Nb-doped TiO2 nanoparticles were prepared by solution synthesis, and utilized as photoelectrode for dye-sensitized solar cell aiming to obtain better photon-to-current conversion efficiency. Nb doping was carried out using two different Nb precursors, and subsequent hydrothermal treatment resulted in the size-controlled (similar to 10 nm) Nb-doped TiO2 nanoparticles with typical ellipsoidal shapes and anatase morphologies. It was observed that NbCl2 precursor resulted in more uniform particle size, while Nb oxalate resulted in relatively broader particle size distributions and higher aspect ratio ellipsoid. Using these nanoparticles, 10 mu m-thick porous inverse opal (IO) photoelectrodes were fabricated by coating the mixed aqueous dispersions of Nb-TiO2 nanoparticles and polystyrene particles of 270 nm diameter on conductive glass followed by thermal sintering. DSSC single cell performance tests revealed that a photoelectrode from 2 mol% Nb- TiO2 obtained from NbCl2 exhibited 20 % enhancement for solar cell efficiency compared to bare TiO2 IO.