We fabricated perovskite based solar cells using CH₃NH₃PbI_3-xCl_x with different hole transporting materials such as Spiro-OMeTAD and P3HT. By tuning the energy level of P3HT and optimizing the device’s fabrication, we reached 9.3% of power conversion efficiency showing that P3HT can be a suitable low cost hole transport material for efficient perovskite based solar cells.

[Di Giacomo et al, J. Power Sources 251, 152 (2014)]