Pure natural aloe vera plant mixed ligands modified cesium lead bromide quantum dots for improved light-emitting performance and stability

This study used hot-injection and ice-water bath methods to air-synthesize perovskite CsPbBr3 quantum dots (QDs-CsPbBr3) doped with aloe vera plant (AV-P). The addition of AV-P does not change the microscopic reorganization of QDs-CsPbBr3, and still maintain the cubic lattice structure. The pristine QDs-CsPbBr3 and AV-P:QDs-CsPbBr3 films, where narrow photoluminescence (PL) bandwidths of 24.88 and 22.65 nm as well as emission peaks at 524 and 521.6 nm, respectively, can be seen, indicating that AV-P:QDs-CsPbBr3 possessed good size monodispersity, high crystallinity and high PL quantum yield (56%) after adding AV-P. In terms of device characteristics, the maximum luminance of 2502 and 3161 cd m−2 achieved in the pristine QDs-CsPbBr3 and AV-P:QDs-CsPbBr3 quantum-dot light-emitting diodes (QDLEDs), respectively, at voltages of 6.5 V and 6 V. Obviously, compared with that of the pristine QDs-CsPbBr3 QDLED, it can be found that the AV-P:QDs-CsPbBr3 QDLED exhibited 26.3% enhancements in the luminance. In addition, AV-P:QDs-CsPbBr3 QDLED displays a turn-on voltage of 3 V and an external quantum efficiency of 0.31%.