Titanium nitride (TiN) or its thermally treated version is incorporated into the gel electrolyte of a dye-sensitized solar cell (DSSC) and the consequent effects are investigated in terms of photovoltaic performance of the cell. The gel electrolyte is essentially prepared by using poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP). With an addition of 3 wt% TiN, the solar-to-electricity conversion efficiency (eta) of the DSSC reaches 5.33% from 4.15% of the cell without TiN. X-ray diffraction (XRD) spectra of thermally treated-TiN (tt-TiN) clearly shows the partial conversion of TiN into TiO2 with both anatase and rutile crystal phases. The DSSC with the incorporation of 3 wt% of tt-TiN into its electrolyte shows a further improved efficiency of 5.68%, with reference to the efficiency of TiN-incorporated DSSC. The cell with 3 wt% of tt-TiN also shows unfailing at-rest stability after more than 1000h. Electrochemical impedance spectroscopy (EIS) is used to obtain charge transfer properties of the cells. Crystallinity and crystalline phases are analyzed by X-ray diffraction (XRD) spectra. Surface morphologies are observed with scanning electron microscopy (SEM). IPCE curves substantiate the variations in short circuit photocurrents. (C) 2010 Elsevier B.V. All rights reserved.