Size and morphology effects of titania on dye-sensitized solar cells performance

Abstract

This study uses commercial titania (P25) to prepare titania nanowires (NWs) using alkali and hydrothermal treatments. Nanosized titania P25 and NWs were used to prepare spray-dried titania P25 (SP25) and spray-dried titania nanowires (SNWs), respectively, using the spray-drying process. These different titania sizes and morphologies were used to fabricate photoelectrodes for dye-sensitized solar cells (DSSCs) and to investigate their effect on cell performance. All prepared titania NWs and SNWs were in the anatase phase after heat treatment at 450°C for 2h. The specific areas for titania with different morphologies were 49.5m2/g for P25, 48.3m2/g for SP25, 42.6m2/g for NWs, and 40.3m2/g for SNWs. The results show that the surface areas decreased when the titania P25 or NWs were processed by spray drying. In optimal conditions, DSSCs prepared from P25+2.5wt.% NWs with a light-to-electric energy conversion efficiency of 5.88% were produced using a simulated solar light irradiation of 100mW/cm2 (AM 1.5).