Large area perovskite light-emitting diodes by gas-assisted crystallization†
Halide perovskites have been gaining considerable attention recently for use in light-emitting applications, due to their bandgap tunability, color purity and low cost fabrication methods. However, current fabrication techniques limit the processing to small-area devices. Here, we show that a facile N2 gas-quenching technique can be used to make methylammonium lead bromide-based perovskite light-emitting diodes (PeLEDs) with a peak luminance of 6600 cd m−2 and a current efficiency of 7.0 cd A−1. We use this strategy to upscale PeLEDs to large-area substrates (230 cm2) by developing a protocol for slot-die coating combined with gas-quenching. The resulting large area devices (9 devices of each 4.46 cm2 per substrate) with three slot-die coated layers exhibit uniform emission with a peak luminance of 550 cd m−2 and a current efficiency of 2.6 cd A−1. The reasons for the reduced performance and improvement routes are discussed. These results mark a vital step towards scalable manufacturing techniques for PeLEDs.
- This article is part of the themed collections: 2019 Journal of Materials Chemistry C HOT Papers and International Year of the Periodic Table : From Pb and Sn Perovskites to the Next Generation