Experimental Investigation of Tin Oxide Blocking Layer for Monolithic Dye Sensitized Solar Cells

This research work was on experimental investigation of Tin oxide blocking layer for dye-sensitized solar with objective targeted at improved power conversion, efficiency and charge recombination that contribute to low current in dye sensitized solar cells. Dye-sensitized solar cells (DSSCs) built upon mesoporous titanium dioxide sensitized with organic dye extracted from dried Hibiscus sabdariffa with three different materials used as blocking layers were fabricated. The dye extract and active layers were characterized by UV-vis spectrophotometer, with the TiO2 sensitized with dye layer showing a band gap of 3.0 eV, and hence could absorb incident solar radiation beyond the Ultraviolet region. Photoelectrochemical properties of the DSSCs were determined using the Newport solar simulator. The best performance among the DSSCs fabricated was obtained for the dye sensitized solar cell fabricated with titanium dioxide as blocking layer with a conversion efficiency of 2.88%. The investigation showed that dye sensitized solar cells fabricated with Tin oxide blocking layer showed lower conversion efficiency when compared to dye sensitized solar cells fabricated with titanium dioxide as blocking layer.