Highly-efficient and stable warm white emission from perovskite/silica composites with photoactivated luminescence enhancement

Abstract

Organic–inorganic hybrid perovskites (OIHPs) with white emission have recently attracted much attention because they can be used as single-component luminescent materials in UV chip driven white-light-emitting diodes (WLEDs). However, low luminescence efficiency and poor stability of OIHPs with warm white emission limits their application in indoor lighting. Herein, Mn-doped and mixed-halide perovskite composites with silica gel have been designed and synthesized. Through optimizing reaction conditions, highly efficient warm white-emissive perovskite composite films with quantum yields of up to 39% and CCTs of less than 3600 K have been obtained. The resultant blend films give very stable warm white emission under continuous UV irradiation, and in a high humidity and temperature environment. A series of UV-driven WLEDs with a CRI of 83–91 and CCT of 2300–4014 K has been realized by using the composite films as single-component luminescent materials. Interestingly, the perovskite powders and composite films display the property of photoactivated luminescence enhancement under 365 nm of UV light. After 15 min of photoactivation, their emissive intensity at 614 nm improved 2.1 and 2.7 times, respectively.