Congeneric Incorporation of CsPbBr₃ Nanocrystals in a Hybrid Perovskite Heterojunction for Photovoltaic Efficiency Enhancement

Organic-inorganic hybrid perovskite materials have had remarkable success in photovoltaics due to their superior optoelectronic properties and compositional abundance. Most advances focus on the improvement of the heterojunction, in which nonperovskite materials are employed at the pertaining interfaces. Herein we demonstrate the modification of perovskite absorber by incorporation of CsPbBr₃ nanocrystals, which is congeneric to the absorber in terms of crystal structure and stoichiometry. It led to significant enhancement in photovoltaic performance in the corresponding devices, which was mainly attributed to the improved carrier dynamics over the resultant heterojunction. Therefore, a different strategy is suggested for further improvement of the perovskite heterojunction by using congeneric materials.