The effect of thermal annealing on the morphology and crystallinity of MAPbBr3 films as well as the performance and long-term stability of PeLEDs were investigated. A continuous perovskite film with high crystallinity was fabricated using a thermal annealing treatment. To obtain uniform and dense MAPbBr3 films, the MAPbBr3 layer used as the emissive layer was deposited onto a PEDOT:PSS-coated ITO/glass substrate by spin-casting a 1:1 molar ratio solution of PbBr2 and MABr in a DMF/HBr cosolvent. The PeLED with a MAPbBr3 film fabricated under optimized thermal annealing conditions exhibited improved device performance and full coverage of the green electroluminescence (EL) at the turn-on voltage because of the high quality of the continuous perovskite layer, as confirmed by scanning electron microscopy (SEM) and inverted optical microscopy. Moreover, the encapsulated PeLED with the MAPbBr3 film prepared under the optimized thermal annealing conditions exhibited excellent long-term stability under ambient conditions.
- long-term stability
- perovskite light-emitting diodes