Ke’s paper entitled “Multifunctional Conjugated Ligand Engineering for Stable and Efficient Perovskite Solar Cells” has been published in Advanced Materials. Read the story here.
We report a novel multifunctional semiconducting organic ammonium cationic interface modifier inserted between the light-harvesting perovskite film and the hole-transporting layer. It is shown that the conjugated cations can directly extract holes from perovskite efficiently, and simultaneously reduce interface non-radiative recombination. Together with improved energy level alignment and the stabilized interface in the device, a triple-cation mixed-halide medium-bandgap solar cell with an excellent power conversion efficiency of 22.06% (improved from 19.94%) and suppressed ion migration and halide phase segregation, which lead to a long-term operational stability, is demonstrated.