Facile one-pot preparation and luminescence mechanism of stable Bi3+-doped Cs2AgInCl6 double perovskite nanocrystals

Lead-free alloyed Cs 2 AgInCl 6 nanocrystals (NCs) are currently considered as a new class of lead halide perovskite alternative due to their less toxicity and excellent intrinsic stability. However, their solution preparation process with oleylamine as ligands are easy to the formation of metallic Ag due to the reduction of Ag + , resulting in poor photoluminescence (PL) performance of NCs. Herein, a facile one-pot solution synthesis strategy was proposed to prepare stable Bi 3+ doped Cs 2 AgInCl 6 NCs via tri-n-octylphosphine (TOP) as co-ligands, and the emission mechanism was further investigated. The prepared Bi 3+ doped Cs 2 AgInCl 6 NCs show broad dual emission bands at around 410 nm and 565 nm, in which the violet emission band is ascribed to the surface defect states, while the yellow emission band of as-synthesized NCs is attributed to the 3 P 1 → 1 S 0 self-trapped excitons recombination of Bi 3+ ions. Due to the introduction of BiCl 6 states after doping with Bi 3+ and well elimination of surface metallic silver by strongly coordinating of TOP, the PL quantum yield of as-synthesized NCs is obviously elevated from 1.25% to 5.10%. The prepared Bi 3+ doped Cs 2 AgInCl 6 NCs exhibit excellent storage stability and light stability, making it a promising single emitter fluorescence material for white light-emitting diode devices.