Effect of small molecule additive on efficient operation of all inorganic polycrystalline perovskite light-emitting diodes
Abstract
Perovskite light-emitting diodes (PeLEDs) have received increasing attentions because of their unique saturated emission color and solution fabrication capability. In this work, we report our effort for attaining high performance cesium lead tribromide (CsPbBr3)-based PeLEDs through controlled growth of the inorganic polycrystalline perovskite emissive layer. The effect of a small molecular additive 2-(4-biphenylyl)-5-phenyl-1,3,4-oxadiazole) (PBD) on the formation of the uniform pinhole free one-step-processed CsPbBr3-based emissive layer was analyzed. The results reveal that the use of the PBD additive in the precursor solution enables suppressing the leakage current in the PeLEDs, realized through improved charge transport and controlled growth of the CsPbBr3-emissive layer. A maximum luminance of 9396 cd/m^2 was realized for PeLEDs prepared using an optimal PBD additive concentration in the perovskite precursor solution, which is >4 times high than that of the control PeLED fabricated using a pure CsPbBr3-precursor solution (2455 cd/m^2).
- This article is part of the themed collection: Electronic Properties and Characterisation of Perovskites