Solar Energy, Vol.191, 663-671, 2019
An investigation on surface modified TiO2 incorporated with graphene oxide for dye-sensitized solar cell
In the present study, titanium dioxide (TiO2) nanoparticles were amine functionalized by using (3-aminopropyl) triethoxysilane (APTES) for the incorporation with graphene oxide (GO) to resolve the rapid agglomeration of nanoparticles. The zeta potentiometer revealed a significant increment of surface charge from 8.31 mV (un-treated) to 34.5 mV (treated) for the TiO2 nanoparticles which promotes strong electrostatic attraction with GO. Electrophoretic deposition technique was then employed for the fabrication of the photoanodes by generating an electric field for the transportation of the composite material. This work aimed to find the optimum loading content of GO-TiO2 for a higher photoconversion efficiency of the dye-sensitized solar cell (DSSC). Among the samples, the sample loaded with 0.5 g TiO2 showed the lowest emission peak intensity (Raman PL) which indicates efficient trapping of photogenerated electrons. By applying the Kubelka-Munk (K-M) expression, the absorbance spectra were converted into Tauc plots through which the aforementioned sample was found to exhibit a band gap energy of 2.91 eV (suitable for light absorption in the visible light region). The electron transfer efficiency for the sample loaded with 0.5 g TiO2 was relatively higher than the other samples in the DSSCs yielding a photoconversion efficiency of 6.86% because of the effective reduction in electron recombination.