Improved Carrier Collection and Hot Electron Extraction Across Perovskite, C60, and TiO2 Interfaces

The use of C60 as an interfacial layer between TiO2 and methyl ammonium lead iodide perovskite is probed to reduce the cur-rent-voltage hysteresis in perovskite solar cells (PSCs) and, in turn, to impact the interfacial carrier injection and recombination processes that limit solar cell efficiencies. Detailed kinetic analyses across different timescales, that is, from the femtoseconds to the seconds, reveal that the charge carrier lifetimes as well as the charge injection and charge recombination dynamics depend largely on the presence or absence of C60. In addition, we corroborate that C60 is applicable in hot carrier PSCs as it is capable of extracting hot carriers generated throughout the early timescales following photoexcitation.