The Effect of FTO Sheet Resistance on the Efficiency of Dye Sensitized Solar Cell

Abstract

In this work, DSSCs have been fabricated successfully using a simpleprocedure without the need for any complicated facilities. The XRD analysis of theTiO2 film confirmed that it has a polycrystalline structure belonging to anatasephase with crystallite size of 12.4 nm. UV-Vis spectroscopy was used tocharacterize the absorbance spectrum of the TiO2 film and Z907 dye. The energygap of the TiO2 film estimated by Tauc’s plot was 3.12 eV. The SEM micrograph ofthe TiO2 film shows that the layer has a spongy shape with reduction in the numberof open pores making easy for dye adsorption and electron transport. The AFMmicrograph and the granularity cumulative distribution chart of the TiO2 film showsthat the average roughness, root mean square roughness and average grain sizewere about 0.356 nm, 0.423 nm and 82.48 nm respectively. The DSSC fabricatedusing glass substrates coated with 8 Ω/ sheet resistance FTO achieved the highestshort circuit density (JSC) and conversion efficiency (η) of 4.069 mA/cm2and1.786 %, respectively. Subsequently, the enhancement in efficiency was ~ 84 %compared with the conversion efficiency of DSSC fabricated using glass substratescoated with 15 Ω/ sheet resistance FTO.