A new method has been developed upon surface treatment of TiO2 photoanode with LiI/NaI to enhance the photocurrent and, subsequently, the performance efficiency of the fabricated dye-sensitized solar cells (DSSCs). Three different concentrations (0.1, 0.25, 0.5 mmol%) of LiI and NaI solutions were used to investigate the effect of this surface treatment in terms of DSSCs device performance. The positive shift in the energy level of TiO2 has been experienced by surface treated devices which is predominantly supported by the decrease in VOC. Further, the introduction of LiI/NaI onto the TiO2 surface resulted reduction in crystallite size means increase in surface area which helps more dye adsorption leading to higher JSC values of the devices. Besides, modification of the conduction band energy level, it also allows the fast electron injection process by shifting the density of states. Thus, this approach offers a simple but efficient route to enhance the photocurrent and efficiency of the DSSCs.
Band Bending Effect of LiI/NaI treated TiO2 Photoanode on Performance of Dye-sensitized Solar Cells
Neitzert, Heinz-Christoph;
2020-01-01
Abstract
A new method has been developed upon surface treatment of TiO2 photoanode with LiI/NaI to enhance the photocurrent and, subsequently, the performance efficiency of the fabricated dye-sensitized solar cells (DSSCs). Three different concentrations (0.1, 0.25, 0.5 mmol%) of LiI and NaI solutions were used to investigate the effect of this surface treatment in terms of DSSCs device performance. The positive shift in the energy level of TiO2 has been experienced by surface treated devices which is predominantly supported by the decrease in VOC. Further, the introduction of LiI/NaI onto the TiO2 surface resulted reduction in crystallite size means increase in surface area which helps more dye adsorption leading to higher JSC values of the devices. Besides, modification of the conduction band energy level, it also allows the fast electron injection process by shifting the density of states. Thus, this approach offers a simple but efficient route to enhance the photocurrent and efficiency of the DSSCs.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
