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.

Keywords:

• TiO₂
• Molarity
• Spin coating
• Sol-gel
• Thickness
• I-V characteristics
• Solar cells

Acknowledgements

This work is based on a presentation originally accepted for and presented at MITC 2015, Penang, Malaysia, 16–17 November, 2015. It was supported by a Research Grant from the Ministry of Education Malaysia and the Research Management Institute (RMI). This work was also supported by the Long-Term Research Grant Scheme for Nanostructures, Nanomaterials and Devices for Fuel Cells and Hydrogen Production [600-RMI/LRGS 5/3 (3/2013)] and the RMI, Universiti Teknologi MARA, Malaysia. The authors thank them for their support. The authors would also like to acknowledge the Department of Biochemistry, College of Science, King Saud University, Kingdom of Saudi Arabia for the research collaboration and support.