Nanostructured composite photoanode for dye-sensitized solar cell.
Lim, Chiew Keat.
Date of Issue2013
School of Electrical and Electronic Engineering
Dye-sensitized solar cell (DSSC) is a new generation of solar cell technology that has the potential for highly photovoltaic conversion efficiency and relatively simple fabrication process at low production cost. DSSC is made up of the sealed sandwich structure of the transparent conducting photoanode and the conducting counter electrode filled with the redox electrolyte. The photoanode is a thick (about 10 µm) mesoporous layer made from the interconnected matrix of wide band gap oxide semiconductor (typically TiO2) nanoparticles. The mesoporous photoanode provides a large surface area for anchoring the sensitizer dye molecules and plays a vital role in transporting the photogenerated electron from the dye sensitizer towards the electrode. An efficient transport of electron from the dye sensitizer through the mesoporous oxide layer is desirable for high charge collection efficiency at the electrode. In this project, two novel approaches were developed in DSSC fabrication to improve the charge transport property in mesoporous photoanode and the charge collection efficiency at the electrode. The improvement in the charge transport property was achieved by incorporating N-doped TiO2 in the mesoporous TiO2 layer of the photoanode. The enhancement in the charge collection efficiency was achieved by utilizing the SnO2 nanorods on Fluorine-doped Tin Oxide (FTO) glass substrate as 3D electrode. The combined effects of these two novel approaches simultaneously enhanced the charge transport property and the charge collection efficiency of the photoanode with an impressive 28 % improvement in the conversion efficiency over the standard DSSC was achieved.