Design and fabrication of novel Tb doped BaTiO3 thin film with superior light-harvesting characteristics for dye sensitized solar cells

Herein propose a high performance dye sensitized solar cell based terbium (Tb) doped barium titanate (BaTiO3) thin films prepared by three different techniques such as chemical bath deposition method (CBD), screen printing (SP) and spray pyrolysis coating (SPC) techniques respectively. XRD, SEM and HRTEM results suggest that tetragonal phase of BaTiO3 with three different morphologies like spherical, nanosheets and nanofibers for CBD, SP and SPC assisted Tb:BTO thin films, respectively. Enhancing the visible light absorption, narrowing the band gap energy and prevent the recombination process of electron-hole pair of SPC assisted Tb:BTO thin films were also examined by UV and PL spectra analysis. Moreover, the SPC assisted Tb:BTO thin films show high surface area (102.5 m(2)/g) and specific porous nature (14.7 nm), studied by N-2 adsorption-desorption analysis. Sandwich type DSSC was fabricated and studied the current-voltage characteristic of all the Tb:BTO thin film photoanode samples. The device utilizing in the SPC assisted Tb:BTO thin film photoanode produced the highest photo conversion efficiency (eta) of 15.15% than compared with CBD assisted Tb:BTO (6.57%) and SP assisted Tb: BTO (8.67%). This is due to highest porosity, surface area, lowest leak current and charge transfer resistance Rct of Tb:BTO photoanode. The improved mechanism of the proposed work is also discussed in detail.