Enhanced Performance of Perovskite Light-Emitting Diodes via Phenylmethylamine Passivation

Organic-inorganic perovskite materials are widely used in the preparation of light-emitting diodes due to their low raw material cost, solution preparation, high color purity, high fluorescence quantum yield, continuously tunable spectrum, and excellent charge transport properties. It has become a research hotspot in the field of optoelectronics today. At present, the nonradiative recombination and fluorescence quenching occurring at the interface between the device transport layer and the light-emitting layer are still important factors limiting the performance of perovskite light-emitting diodes (PeLEDs). In this work, based on CH₃NH₃PbBr₃ perovskite, the effects of parameters such as precursor solution, anti-solvent chlorobenzene (CB), and small amine molecule phenylmethylamine (PMA) on the performance of perovskite films and devices were investigated. The research results show that adding an appropriate amount of PMA can reduce the grain size of perovskite, improve the coverage of the film, enhance the crystallinity of the film, and increase the fluorescence intensity of the perovskite film. When the PMA content is 0.050 vol.%, the maximum luminance of PeLEDs is 2098 cd/m² and the maximum current efficiency is 1.592 cd/A, which is greatly improved by 30% and 64.8% compared with the reference device without PMA doping. These results suggest that an appropriate amount of PMA can effectively passivate the defects in perovskite films, and inhibit the non-radiative recombination caused by the traps, thereby improving the optoelectronic performance of the device.