[18a-PB1-1~20] 9.2 Nanoparticles, Nanowires and Nanosheets

▲ [18a-PB1-18] Lanthanum doped TiO₂ mesoporous spheres as photoanode for DSSC applications

〇(M2)Kamaljeet Singh¹, Harish Santhanakrishnan^1,2, Masaru Shimomura¹ (1.Shizuoka Univ., 2.SRM Univ.)

Keywords:Mesoporous TiO2, DSSC

Since first proposed by O’Regan and Gratzel, Dye-Sensitized Solar Cells (DSSCs) has gained a lot of attention due to its simplicity and low-cost fabrication technique. It is typically made up of fluorine-doped tin oxide (FTO) layer, photoanode, dye, hole transporting material (HTM) and counter electrode. The photoanodes are typically made up of wide bandgap semiconductors like TiO₂ and ZnO. The TiO₂ is most commonly used photoanode for DSSCs application due to its strong affinity for organic molecules, similar band alignment with commonly used dyes, non-toxicity, low-cost and photostable. One method of increasing efficiency of DSSC is by increasing dye concentration on TiO₂ photoanode. Generally, a dye molecule attaches to surface Ti atoms, hence, dye loading can be increased by increasing oxygen vacancies on the TiO₂ surface. In order to create more oxygen vacancies on surface of TiO₂, Lanthanum-doping into the TiO₂ crystal structure was performed. Typically, the La-O bond is stronger than the Ti-O bond. Thus, it can extract oxygen atoms from TiO₂ and create oxygen vacancies in the process.