Effect of nanoporous In2O3 film fabricated on TiO2-In2O3 photoanode for photovoltaic performance via a sparking method

A simple and inexpensive sparking method was used to deposit body-centered cubic In2O3 film on TiO2 photoanode for 30–180 min for dye-sensitized solar cells (DSSCs). The effect of nanoporous In2O3 film on photovoltaic performance was investigated. The efficiency of TiO2-In2O3 photoanode with the sparking time for 120 min was the highest of 3.40 and 8.6% rise in conversion efficiency comparing to the TiO2 photoanode device, due to the increasing in short-circuit current density (Jsc) and electron lifetime (Teff). In this research, Jsc improvement was caused by increasing surface area for adsorbed dye molecules. TiO2-In2O3 photoanode exhibited low resistance of charge diffusion (Rct1) at the interface of the redox electrolyte/Pt counter electrode and/or electrical contact between In2O3 nanoparticles by providing an efficient pathway for photogenerated electrons in the DSSCs. Furthermore, the long-term stability of DSSCs showed that TiO2-In2O3 photoanode with 120 min sparking period exhibited the highest efficiency comparing with the pure TiO2 photoanode.