Red amplified spontaneous emission of polymer passivated perovskite quantum dots

All-inorganic CsPbX3 (X = Cl, Br, I) perovskite quantum dots have excellent luminescence properties and are a new kind of display material and laser gain medium with great application potential. In this paper, CsPbBr1.2I1.8 red quantum dots with luminescence peak at 640 nm were prepared and the CsPbBr1.2I1.8 quantum dot films were coated with three kinds of polymers with different functional groups: polymethyl methacrylate (PMMA), polyiso-butyl methacrylate (PIBMA) and polystyrene (PS). The amplified spontaneous emission performance of CsPbBr1.2I1.8/PMMA,CsPbBr1.2I1.8/PIBMA and CsPbBr1.2I1.8/ PS composite films were studied. The results show that the polymer passivation improves the water stability of quantum dot films. Moreover,the C=O in PMMA and PIBMA passivates the unco. ordinated Pb2+ on the surface of quantum dots,enhancing the photoluminescence intensity of QD films. Furthermore,the amplified spontaneous emission threshold of CsPbBr1.2I1.8/ PIBMA film is as low as 81 mu J center dot cm(- 2) under nanosecond laser pumping at 532 nm. The stability is improved,demonstrating its potential as a novel gain medium.