Fabrication and analysis of photoelectrode based on TiO2 nanotube/phosphor mixed TiO2 nanoparticle film for dye-sensitised solar cells

Abstract

Dye-sensitised solar cells (DSSCs) have attracted scientific attention because of their advantages over former Si-based devices, such as flexibility, light weight, low cost, and low toxicity of the manufacturing process. Generally, DSSCs are composed of a titanium dioxide (TiO2) layer as the working electrode, on which an anchored organic dye is absorbed, a Pt layer as the counter electrode, and an electrolyte containing a redox couple (I-/I-3(-)) between them. However, a number of problems remain to be solved to improve their efficiency. We fabricated a hybrid photoelectrode comprising a TiO2 nanotube (TNT)/phosphor mixed TiO2 nanoparticle film on a TiO2 passivating layer to improve the dye adsorption and charge transport as well as reduce the electron recombination. In this paper, we describe the enhancement of the photovoltaic performance of a DSSC obtained via using a TiO2 passivation layer and a TNT/phosphor mixed TiO2 paste photoelectrode. The DSSCs with FTO glass pretreated in 90 mM TiCl4 for 90 min exhibited the highest efficiency of 5.98% and a JSC of 13.17 mA/cm(2).