InGaN nanohole arrays coated by lead halide perovskite nanocrystals for solid-state lighting

Down-conversion of light via phosphors is central to the generation of white and multi-color emission for solid-state lighting. Lead halide perovskite nanocrystals (NCs) are viable contenders to phosphors as they offer higher emission yields with narrower linewidth and facile synthesis and compositional tunability across the visible. Herein, we employ green-emitting CsPbBr3 and FAPbBr3 and near infrared-emitting FAPbI3 NCs to efficiently down-convert the emission of InGaN/GaN structures. The nitride wafers are patterned into nanohole arrays which are filled by the perovskite NCs to minimize the nitride-NC separation while increasing the heterointerfacial area, thus improving light conversion via both non-radiative resonant and radiative energy transfer. The efficient quenching of the nitride emission dynamics in the presence of the NC overlayers accompanied by a concurrent increase of the NC emission, provides evidence of efficient light down-conversion with efficiencies as high as ~83±6% in the green and ~74±5% in the near-IR.