Different mesoporous titania films for solid-state dye sensitised solar cells

Abstract

The nature and morphology of titanium dioxide films play a significant role in determining the overall efficiency of the dye sensitised solar cell (DSSC). The influence of three different nanocrystalline titania films, prepared from three different routes, namely sol–gel (FMF), thermal (P-25), and colloidal-microwave process (CMP), on the performance of solid-state dye sensitised solar cells was studied and discussed here. The difference in the preparation of nanotitania leads to different surface area, pore size and morphology of the mesoporous films. FMF–TiO 2 displayed the highest efficiency and IPCE in DSSC among the other two because it possessed pure anatase phase, optimum surface area, pore volume and pore diameter; and well-connected network of individual nanoparticles. P-25 films exhibited pore structural and morphological features similar to FMF films but it displayed lower efficiency than FMF–TiO 2 due to the presence of small percentage of rutile phase besides major anatase phase. Although, CMP films had high surface area, it possessed smaller pore diameter and pore volume besides agglomerates and macropores leading to lower efficiency. The work clearly demonstrates the optimal pore and morphological structures required for efficient functioning of solid-state dye sensitised solar cell.