Highly emissive Sb3+-doped Rb2InCl5·H2O perovskites: cost-effective synthesis, luminescence, and its application

Abstract

Zero-dimensional (0D) lead-free halide perovskites are emerging as promising light-emitters, which can be applied as light conversion materials for illumination and display. Herein, we prepared a series of Sb³⁺:Rb₂InCl₅·H₂O perovskites by a simple and efficient coprecipitation method. The Rb₂InCl₅·H₂O perovskite gives no emission due to the parity-forbidden transition. When Sb³⁺ is doped into Rb₂InCl₅·H₂O, radiative transition occurs. Under 365 nm excitation, the Sb³⁺:Rb₂InCl₅·H₂O perovskites show an intense orange-red emission peak at 615 nm, ascribed to the ³P₁ to ¹S₀ transition of Sb³⁺. The brightest luminescence of Sb³⁺:Rb₂InCl₅·H₂O was achieved by doping 40%Sb³⁺, with a high photoluminescence quantum yield (PLQY) of 62.1% and an external quantum efficiency (EQE) of 30.2%. Furthermore, the prepared Sb³⁺:Rb₂InCl₅·H₂O perovskite exhibits a distinguished thermal stability. At 150 °C, its PL intensity remains 68% of that measured at room temperature, with a high thermal activation energy of 0.184 eV. By combining Sb³⁺:Rb₂InCl₅·H₂O with a blue-emitting Eu²⁺:BaMgAl₁₀O₁₇ (Eu²⁺:BAM) phosphor, bright warm-white light with a color rendering index of 88 and a correlated color temperature of 3242 K was achieved. To sum up, the prepared Sb³⁺:Rb₂InCl₅·H₂O orange-red perovskites have the advantages of suitable excitation and emission peak positions, high emission intensity, high PLQY and EQE, excellent stability, and environmental friendliness, making them very attractive in the field of lighting and displays.