Enhanced performance of a dye-sensitized solar cell with the incorporation of titanium carbide in the TiO2 matrix

Abstract

The effects of incorporation of various weight percentages of titanium carbide (TiC) into TiO₂ matrices on the photovoltaics of the respective dye-sensitized solar cells (DSSCs) were investigated. It is established through relevant photographs, XRD and EDX analysis that TiC was partially converted into anatase TiO₂ (a-TiO₂) when the TiC was sintered at 450 °C. With the incorporation of 3.0 wt% of the TiC in the TiO₂ film, the solar-to-electricity conversion efficiency (η) of the cell reached 7.56% from its value of 6.61% with a bare TiO₂ film. “In situ” incorporation of this TiC/a-TiO₂ composite in the commercial TiO₂ is considered as the basis for enhanced cell efficiency of the benefited cell. The variations in J_SC, FF, and V_OC are explained by analyzing the data of dark currents, UV-absorption spectra, transparency spectra, and electrochemical impedance spectra (EIS) which were obtained under illumination and darkness. Enhancement in the V_OC for the promoted cell is explained through pertinent electron lifetime in the TiO₂ film, which was obtained by using laser-induced photo-voltage transient studies. Electron diffusion coefficient was also measured by using laser-induced photo-current transient studies.