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 degrees 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. (C) 2011 Elsevier Ltd. All rights reserved.