Oxygen-plasma processed Spiro-OMeTAD toward high performance for perovskite solar cell

Efficient perovskite solar cell was achieved using a small hole transport material, Spiro-OMeTAD, after oxygen plasma treatment. It was demonstrated that the plasma treatment of hole transport layer for the solids state perovskite solar cell was enhanced power conversion efficiency. Reason for enhancing the cell performance of solar cell was good match of homo energy level between perovskite and Spiro-OMeTAD. It leads to transfer well hole carrier at Active/HTL interface. This study obtained highly improved performance by a current density of 25.4 mA/cm2, an open-circuit voltage of 1.02 V, and a fill factor of 60.2%, which resulted showed above 15% of cell efficiency. [Display omitted] •We applied the O2 plasma treatment at Spiro-OMeTAD of HTM.•The rate of recombination reduced after plasma process due to the energy level was good matched mutually.•We achieved 15.6% power conversion efficiency and this process will be useful for solar cell industry.