Solar cells using spray coated a-axis grown F: SnO2 thin films

Devices based on a-axis growth are easier to engineer as they aid continuous process flow. We have achieved the deposition of highly a-axis-oriented Fluorine-doped SnO2 (F: SnO2) thin films on a glass substrate using the spray-pyrolysis technique. X-ray diffraction and Raman analysis proved that the spray-pyrolysis-grown F: SnO2 thin films possessed a tetragonal crystal structure matching the rutile phase of SnO2. SEM and AFM analysis of the F: SnO2 films showed uniform surface morphology. The room-temperature photoluminescence spectra exhibited a broad UV photoluminescence band centered at ∼390 nm. With UV–visible absorption studies, the optical band gap energy reduction corresponded with increased fluorine doping concentrations. From Hall measurements, we could deduce that the optimized a-axis-oriented FTO had a resistivity of ∼0.47 × 10−3 Ωcm, Hall mobility of 31.06 cm2V−1s−1, and carrier concentration of 71.32 × 1019/cm3. Dye-sensitized solar cells with structure “F: SnO2/TiO2/Eosin-Y dye + electrolyte/Graphite/F: SnO2” consisting of the highly a-axis oriented F: SnO2 films outperformed their counterparts. •Device-grade spray-coated a-axis-oriented FTO thin films have been obtained.•Surface wettability measurements indicate a change over from hydrophobic to hydrophilic nature.•The sheet resistance is found to be 6 Ω/cm2 meeting the specific needs for photovoltaic applications.•DSSC consisting of the highly a-axis oriented F: SnO2 films outperformed their counterparts.