The effect of different concentration of TiO2 in solution prepared by sol-gel method on morphology and I-V characteristics for organic solar cell applications

Abstract

TiO2 is a well-known material especially for potential applications in organic solar cells. In this research the objective was to achieve high current-voltage (I-V) characteristics that will improve electron migration. The nanostructured TiO2 was deposited onto a glass substrate using the well-known sol-gel spin coating method. Eight TiO2 solutions with different molarity were tested for their performance as the electron conductor layer in organic solar cells. The surface topology and morphology of nanostructured TiO2 was observed using AFM and FESEM. The electrical properties were investigated by using two probe I-V measurements to study the electrical resistivity behaviour, hence the conductivity of the film. The results showed the lower the molarity of TiO2, the more uniform is the surface achieved, and the better the I-V characteristics for solar cell application. As predicted, the best thin film characteristic is the 0.01M concentration which will be applied in future organic solar cell work.