Bromide ions substitution-induced photoluminescence tuning in Cs2NaInCl6:Sb3+double perovskite

Compositional tune and doping/alloying routes have become the research focus for tailoring optical features of lead-free metal halide double perovskites to advance the development of solid-state lighting and display applications. Cs2NaInCl6 double perovskite is receiving tremendous attention owing to its excellent optical properties. In this paper, we have successfully obtained the lead-free Cs2NaInCl6-xBrx:Sb3+ perovskites using the hydrothermal method. Via the substitution of bromine ions for chloride ions in Cs2NaInCl6:Sb3+, a tunable emission from 445 nm to 480 nm was realized. The X-ray diffraction, scanning electron microscope, UV-vis absorption spectra, PL spectra, TRPL spectra, air stability and thermal stability were investigated in detail. The sample shows an admirable air stability and excellent thermal stability. The results demonstrate that the cyan-emitting Cs2NaInCl6-xBrx:Sb3+ perovskites can be applied to white LEDs, especially for the full-spectrum LED illumination.