Preparation of TiO 2/NiO composite particles and their applications in dye-sensitized solar cells

Abstract

This study investigates the applicability of n-type TiO 2 and p-type NiO on the FTO-glass (Fluorine doped tin oxide, SnO 2:F) substrate of the working electrode in a dye-sensitized solar cell (DSSC). The working electrode was designed and fabricated by depositing a film of TiO 2/NiO composite particles, which were prepared by mixing the Ni powder with TiO 2 particles using dry mixing method, on a FTO-glass substrate using a spin coating process. The working electrode was then immersed in the solution of N-719 (Ruthenium) dye at a temperature of 70 °C for 6 h. Moreover, a thin film of platinum (Pt) was deposited on the FTO-glass substrate of the counter electrode using an E-beam evaporator. Finally, the DSSC was assembled, and the short-circuit photocurrent, the open-circuit photovoltage and the power conversion efficiency of DSSC were measured using an I– V measurement system. This study also examined the effects of the mass ratio of TiO 2 to Ni and the number of coating of TiO 2 particles (or TiO 2/NiO composite particles) colloid on the power conversion efficiency of the DSSC. Most importantly, this study shows that the power conversion efficiency of the DSSC with TiO 2/NiO composite particles (3.80%) substantially exceeds that of the conventional DSSC (3.27%) due to the effects of the NiO barrier and the n–p junction.