Photo-conversion efficiency measurement of dye-sensitized solar cell using nanocrystalline TiO2 thin film as photo-anodes

• The photo-anode of nano-crystalline TiO2 is derived by sol–gel process.
• 6–10 nm TiO2 particles are synthesized from modified precursor of titanium isopropoxide.
• The deposition of thin film on ITO glass substrates is done by repetitive spin coating process.
• 6.7% photo-conversion efficiency is observed with ∼5.0 μm thin film of TiO2.

Nanocrystalline TiO2 has been synthesized through sol–gel process using precursor of modified titanium isopropoxide with acetylacetone and diacetyl monoxime. The transparent photo anodes of nanocrystalline TiO2 thin film on Indium Tin Oxide (ITO) glass have been made from different modified precursor of titanium isopropoxide using the spin coating technique. The nanostructures of TiO2 are in the order of 2–4 nm in the sol before annealed thin films. The spin coated TiO2 film is annealed at 350 °C and shows a growth of 8–10 nm in both the cases. The before and after annealed thin film of TiO2 have been characterized by XRD, AFM, HRTEM and UV–VIS. These thin films have been tested for use as electrodes in dye sensitized solar cells and the conversion efficiency of the assembled cell comprising of ∼5 μm thickness is found in the order of 6.7%.

(a) HRTEM and (b) SAED images of green TiO2 colloidal sols modified with acetylacetone and (c) the fringe pattern of annealed particles at 450 °C peeled from thin films indicates the crystalline anatase phase of TiO2 is suitable for photo-anodes of DSSC cell. The crossed link network structure developed by repetitive spin coating is good for (d) photo-conversion efficiency even in very smaller thickness.Figure optionsDownload as PowerPoint slide