Using the low-temperature processing of different organofunctional silanes like TEOS, GPTS, and MPTS to incorporate within TiO2 network, dye-sensitized solar cells (DSCs) processed at low temperatures were obtained. The UV-cured MPTS-modified layer exhibited better performance over the TEOS and GPTS, where better mechanical stable layer is achieved in addition to better interconnection between the TiO2 nanoparticles. The J-V characteristics of the DSC composed of silane-based layer showed that the improved cell performance was due to the high photocurrent density accompanied with more dye adsorption and higher charge injection from TiO2 to FTO substrate resulting from the formation of an ohmic contact with the substrate. The highest conversion efficiency attained for MPTS-TiO2 layer cured with UV and followed by heating at 300°C was %, which is 2.8 times better than the GPTS-based layer. 1. Introduction The increasing global demands of clean energy is becoming one of the major scientific challenges for scientists, economists, and politicians [1], as the combustion of fossil foils has produced widespread environmental damage [2]. Therefore, the Sun as an abundant source of energy represents the ideal source of clean energy, which has a solar flux deposited on the surface of the earth within one hour as much as the global power usage. However, the high production cost compared with the fossil foils has retarded the widespread commercialization of this alternative energy. There have been intensive investigations for higher efficiency and cost effective conversion of solar radiation to electricity. Silicon-based solar cell technologies are currently the widely used commercial photovoltaic technology; however, the nonsilicon photovoltaic thin films are a major competitor with less cost and more flexibility than traditional solar cells [3]. One of the most promising technologies is the dye-sensitized solar cells (DSCs), which have attracted much attention as they offer the possibility of extremely inexpensive and efficient solar energy conversion with flexible routes of production. The maximum reported efficiency since the first report published by O’Regan and Gr？tzel in 1991 [4], is with a current record of ~11–13% [5–12]. DSC is a mimic of the photosynthesis and a physical separation between photon absorption and charge percolation process. The light is absorbed by a molecular dye, that is attached to the surface of semiconducting thick layer (10–15？μm) deposited on transparent conducting oxide (TCO) electrode. The excited dye rapidly injects an electron
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