High-Performance Green Light-Emitting Diodes Based on MAPbBr₃–Polymer Composite Films Prepared by Gas-Assisted Crystallization

Abstract

The morphology of perovskite films has a significant impact on luminous characteristics of perovskite light-emitting diodes (PeLEDs). To obtain a highly uniform methylammonium lead tribromide (MAPbBr) film, a gas-assisted crystallization method is introduced with a mixed solution of MAPbBr precursor and polymer matrix. The ultrafast evaporation of the solvent causes a high degree of supersaturation which expedites the generation of a large number of nuclei to form a MAPbBr-polymer composite film with full surface coverage and nano-sized grains. The addition of the polymer matrix significantly affects the optical properties and morphology of MAPbBr films. The PeLED made of the MAPbBr-polymer composite film exhibits an outstanding device performance of a maximum luminance of 6800 cd·m and a maximum current efficiency of 1.12 cd·A. Furthermore, 1 cm area pixel of PeLED displays full coverage of a strong green electroluminescence, implying that the high-quality perovskite film can be useful for large-area applications in perovskite-based optoelectronic devices.

High‐Performance Perovskite‐Based Blue Light‐Emitting Diodes with Operational Stability by Using Organic Ammonium Cations as Passivating Agents

“…The energy‐level values for ITO, PEDOT:PSS, TFB, TPBi, and Al/LiF were obtained from the literature. [ 28–30 ] Moreover, to define the energy‐levels of the perovskite films with different passivating agents, the valence band maximum (VBM) values of the perovskite films were confirmed by ultraviolet photoelectron spectroscopy (UPS) (Figure S4, Supporting Information). The VBM values were calculated by adding the work functions to the energy offsets of the VBM region.…”

Halide‐Perovskite Resonant Nanophotonics

“…This work was supported by the Ministry of Education and Science of the Russian Federation (projects 14.Y26.31.0010 and 16.8939.2017/8.9), the Australian National University, and the Australian Research Council. The authors also acknowledge a partial support from the Welch Foundation (grant [16][17].…”

Efficient and Stable Quasi‐2D Perovskite Solar Cells Enabled by Thermal‐Aged Precursor Solution

“…It suggests that the improvement in crystallinity of the perovskite film can be obtained by TAPS, such as bigger crystalline grains according to the Scherrer formula. [ 24 ]…”

“…It suggests that the improvement in crystallinity of the perovskite film can be obtained by TAPS, such as bigger crystalline grains according to the Scherrer formula. [24] In light of the perovskite precursor solution dispersed with colloids rather than a pure solution, we consider that the colloidal particles can function as heterogeneous nucleation sites to grow into bulk structures in solutions, which in turn influences the perovskite film morphology and crystalline properties. [25] In this context, we carried out dynamic light scattering (DLS) measurements on the precursor solutions to interpret the different qualities of quasi-2D perovskite films.…”