Energy harvesting of flexible and translucent dye-sensitized solar cell fabricated by laser assisted nano particle deposition system

A cost-effective way of fabricating flexible and translucent dye-sensitized solar cell (DSSC) was demonstrated by forming TiO2 layer for photo-electrode via laser assisted nano particle deposition system (La-NPDS). In the La-NPDS, TiO2 particles are accelerated through a nozzle toward the substrate beyond the speed of sound while sintering is being induced concurrently with laser treatment. A uniform and 10.55 μm-thick TiO2 film was deposited onto indium tin oxide-polyethylene terephthalate (ITO-PET) substrate via La-NPDS using 15 nm-diameter TiO2 particles. In situ laser sintering of TiO2 was found to improve the efficiency of DSSC from 1.05% to 1.92%. Moreover, short circuit current and fill factor of DSSC are significantly increased by laser treatment due to close linking among adjacent particles. The necking among particles decreases the surface area of the laser treated TiO2 layer, resulting in decrease of the series resistance and higher short circuit current.The feasibility of the fabricated DSSC as an energy harvesting unit for wireless sensor network was evaluated. Three 1 cm × 1 cm DSSC modules successfully demonstrated as a stable power supply when combined with maximum power management unit under dim light down to 130 mW/cm2.