Crystalline structure and morphology of TiO2 thin films deposited by means of hollow cathode plasma jet with supporting anode

TiO2 thin films with developed structure were deposited by means of a hollow cathode plasma jet (HCPJ) in a DC regime with a supporting anode. The influence of the plasma temperature on the surface morphology and crystalline structure of the thin films under different deposition conditions was studied. Diagnostics of the thin films structure was carried out using XRD, SEM, EDX and TEM methods. One batch of samples was annealed at a temperature of 400 °C in atmospheric conditions as a comparison with the crystalline structure and morphology of unannealed samples. The presence of two crystalline polymorphs of rutile and anatase in the films was discussed. The vacuum system was improved for an extended deposition of non-conductive materials without terminating the discharge and cleaning of the deposition chamber. The aim of this investigation was to prepare the vacuum system for the fabrication of photo electrodes which are the main functional part in dye-sensitized solar cells. The test DSSCs (dye-sensitized solar cells) were prepared from low-cost materials (raspberry/hibiscus natural dye-sensitizers and candle soot counter electrode) in order to check the quality of the films, with a highest conversion efficiency η = 0.66% and a fill factor FF = 62%.