Positive effects in perovskite solar cells achieved using down-conversion NaEuF4 nanoparticles

In this work, NaEuF4 nanoparticles (NPs) with high dispersity and uniformity were synthesized using a hydrothermal method and introduced into the TiO2 mesoporous layer of perovskite solar cells (PSCs) for testing as high efficiency, downconversion materials. NaEuF4 can convert high-energy photons into low-energy photons for absorption by CH3NH3PbI3 and generation of more electron–hole pairs; we tested the hypothesis that this would extend the sunlight absorption range and improve the photovoltaic performance of PSCs. When NaEuF4 NPs were incorporated into TiO2 mesoporous layers, PSCs achieved power conversion efficiencies of 14.51%, which were better than those of the control PSCs. The use of NaEuF4 NPs for improving PSC photovoltaic performance, as shown herein, could encourage the greater use of solar energy.