Silica modification of titania nanoparticles for a dye-sensitized solar cell

Nanocomposites of commercially available titanium oxide (TiO2) nanoparticles (P25) and a silane coupling agent, methacryloxypropyltrimethoxysilane (MPTS), were incorporated into a homogeneous porous material after UV treatment and heating at 450 °C in the air. A dye-sensitized solar cell utilizing this UV-polymerized MPTS-modified sample exhibited significant enhancements in total performance when compared with an analogous cell prepared without MPTS. The photovoltaic enhancement was mainly achieved due to a significant increase in photocurrent density. This improvement is believed to be caused by the increased contact achieved between the small nanoparticles when suspended in a homogeneous, multiporous structure, which in turn would optimize the paths for electron transport. The larger surface area and pore volume resulted in an increase in the dye uptake amount and in the fast redox activity of the electrolyte, enhancing dye regeneration. Furthermore, the measured diffuse reflectance indicated greater light scattering inside the TiO2 multiporous structure.

► Silica coupling agent was used to modify the surface of titanium oxide nanoparticles, showing superior performance compared with the unmodified one. ► The modified DSC showed an increase of the dye uptake due to the larger surface area and optimized paths for electron transport. ► The modified DSC exhibited an enhancement of the light scattering inside the TiO2 multiporous structure.