Preparation and characterization of TiO₂ nanostructures by changing the parameters of trichloroaniline concentration, pH and annealing for dye-sensitized solar cell application

Mesoporous Titanium dioxide (TiO₂) sphere, nanosheet and nanoparticle were synthesized by a simple wet chemical method using Trichloroaniline (TCA) as a capping agent. The presence of a lone pair of electrons in the TCA is used to modify the TiO₂ structure when it is added with different amounts of ratios. The as-synthesized TiO₂ nanostructures were characterized by powder X-ray diffraction, Raman spectroscopy (FT-Raman), ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy and transmission electron microscopy. The anatase phase of TiO₂ was confirmed by Powder X-ray diffraction and Raman spectroscopy. The particle size of TCA-capped TiO₂ was reduced when compared with the sample without TCA capping. FTIR results demonstrated the TiO₂ nanoparticles were capped by the TCA molecule. The impact of different TiO₂ nanostructure morphology for DSSCs was investigated. The photoanode cells were fabricated with mesoporous spheres and mixed morphology of TiO₂ nanoparticle and nanosheet. Their optimal efficiencies were found to be 5.537 and 1.539%, respectively. Mesoporous spheres coated photoanode cells reached the maximum efficiency when compared to that of the mixed morphology of nanosheet with nanoparticle-coated photoanode. The enhanced performance of mesoporous spheres coated photoanode cells is due to the anatase phase of TiO₂ with high crystallinity and interconnected mesoporous network.