Preparation, electrochemical, photoelectrochemical and solid-state characteristics of indium-incorporated TiO2 thin films for solar cell fabrication

Titanium dioxide thin films were prepared by the spray-pyrolysis technique, which permitted the convenient incorporation of foreign materials into the oxide matrix during its formation. Pure and indium-incorporated firms of different thickness were prepared. The presence of indium in the TiO2 film affected the characteristics of that material. The effect of incorporation was reflected in the improvement of the properties of the n-Si/oxide heterojunction. The prepared n-Si/TiO2-In solar cells exhibited better fill factor and solar conversion efficiency than those with pure TiO2. The electrochemical properties of the prepared oxide films revealed that the charge transfer step at the oxide/electrolyte interface leads to the deterioration in quality of the photoanode. The improved characteristics of the heterojunction n-SiO2/oxide in the presence of indium incorporation offset the limitation of the photoelectrochemical cell due to the slow charge transfer step at the TiO2/electrolyte junction.