Chlorinated fluorine doped tin oxide electrodes with high work function for highly efficient planar perovskite solar cells

Perovskite solar cells (PSCs) demonstrate excellent high efficiencies over 20% and potential for a highly scalable manufacturing process. The work function of a transparent electrode (e.g., fluorine doped tin oxide, FTO) plays a critical role in the extraction and collection of electrons in PSCs. In this work, a chlorinated FTO (Cl-FTO) electrode with a high work function is used to fabricate a planar PSC at a low temperature of 100 degrees C with an optimal efficiency of 13.39% for a great improvement of 49% than plain FTO based cells. The change in the work function of FTO and Cl-FTO can reach up to 0.6 eV. The enhancement scientific insight is further explored, indicating that the increased work function of Cl-FTO provides well-matched energy levels between FTO and the CH3NH3PbI3 active material, facilitating the electron extraction and collection. Published by AIP Publishing.