Improved photovoltaic performance of dye‐sensitized solar cells using dual post treatment based on TiCl 4 and urea solution

An effective and efficient photovoltaic performance is significantly affected by the interface between different constituents of dye sensitized solar cells (DSSC). A novel dual post treatment of TiCl 4 and urea solutions on different layers of TiO 2 electrode is addressed and the TiO 2 particle morphology, dye‐adsorption amount on the TiO 2 electrode and the photovoltaic performance of the DSSC based on those electrodes are characterised in this work. TiCl 4 treatment can form more binding site on TiO 2 particles and urea treatment structures a thin layer of g‐C 3 N 4 on the surface of TiO 2 particles. This strategy can not only effectively increase the dye‐adsorption for light‐harvesting, but also facilitate the electron transfer through inhibiting the charge recombination between TiO 2 and electrolyte, and moreover, it provides excess electrons for the photoanodes. The DSSC fabricated from TiO 2 electrode processed with urea treatment on the sixth layer exhibited the highest power conversion efficiency of 8.94% with a short current density J sc of 24.09 mA cm –2 , an open circuit voltage V oc of 583 mV and a fill factor of 63.8.