300 keV cobalt ions irradiations effect on the structural, morphological, optical and photovolatic properties of Zn doped TiO2 thin films based dye sensitized solar cells

Abstract Dye Sensitized Solar Cell (DSSC) is a potential too to convert solar energy into electrical energy due to its low cost, ease in synthesis and higher photo electron conversion efficiency (PEC) in contrast with conventional silicon solar cell. The photo-electrode of DSSC is a key component which is responsible for collection and transportation of electrons through the circuit. Sol-gel route was adopted to manufacture photo anodes of 1% Zinc doped titanium dioxide (Zn–TiO2) where FTO glass was used as substrate. These photo anodes were irradiated by 300 keV Cobalt (Co) ions with different fluence rates as 2 × 104 atomscm-2s-1 and 4 × 104 atoms cm-2s-1. We investigated the anatase phase of TiO2 using the Raman spectra which also showed that Zn and Co are completely doped in TiO2. UV–visible spectroscopy showed that band gap of films was decreased by doping and ions implantation. Maximum reduction in band gap is observed at the fluence rate of 4 × 104 atoms cm-2s-1 i.e. 2.77 eV. SEM micrographs showed that the film irradiated with Co ions with fluence rate of 2 × 104 atoms cm-2s-1 have maximum porosity which supports the maximum dye loading on the surface due to which the efficiency of DSSC is enhanced. In all cells, N719 dye is used as sensitizer. The solar simulator results indicated the higher efficiency up to 3.78% is achieved by 300 keV cobalt ions irradiation with fluence rate of 2 × 104 atoms cm-2s-1. The present work shows that the appropriate percentage of Co ions in Zn–TiO2 layer plays a significant role to escalate the effectiveness of DSSC.