Enhanced Excitonic Nature of MAPbBr₃ Nanocrystals in Nanoporous GaN

Blue gallium nitride (GaN) light‐emitting diodes (LEDs), combined with red/green fluorescent converters, have broad potential for display applications. Metal halide perovskites now show excellent luminescence properties and may be suitable as light converters. Here a simple solution‐processed method is reported to prepare a methylammonium lead bromide (MAPbBr 3 ) nanoporous GaN composite. Fast (within 2 ps) energy transfer is demonstrated from photoexcited nanoporous GaN to encapsulate MAPbBr 3 nanocrystals, as observed by transient absorption spectroscopy. The spatial confinement of the perovskite within the nanoporous GaN is shown to increase the perovskite radiative recombination rate. These results offer guidelines for developing high‐performance perovskite/nanoporous GaN optoelectronics.