Short-term light soaking effect on dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) are one of the most promising third generation solar cells and have been regarded as a competitive alternative to the conventional silicon-based photovoltaic devices due to their relatively low production cost. Light soaking effect is an intriguing phenomenon that exists in DSSCs, which refers to the enhancement of the electrical parameters in the cells after being exposed to light soaking. In this paper, we report on the variation in the electrical parameters of DSSCs under continuous exposure to a simulated solar irradiation for a period up to 6h. Increments of Jsc and Voc in DSSC were observed after 6h of light soaking, which led to improved efficiency from 3.87% to 4.50%. The improvements may be ascribed to the formation of electron trapping states below the TiO₂ conduction band edge, which facilitated the charge carrier transport.