Hole Transport Layer Free Perovskite Light-Emitting Diodes With High-Brightness and Air-Stability Based on Solution-Processed CsPbBr3-Cs4PbBr6 Composites Films

Fang Yuan; Min Zhang; Chunrong Zhu; Xiaoyun Liu; Chenjing Zhao; Jinfei Dai; Hua Dong; Bo Jiao; Xuguang Lan; Zhaoxin Wu

doi:10.3389/fchem.2022.828322

Hole Transport Layer Free Perovskite Light-Emitting Diodes With High-Brightness and Air-Stability Based on Solution-Processed CsPbBr₃-Cs₄PbBr₆ Composites Films

Front Chem. 2022 Jan 21:10:828322. doi: 10.3389/fchem.2022.828322. eCollection 2022.

Authors

Fang Yuan¹, Min Zhang¹, Chunrong Zhu¹, Xiaoyun Liu¹, Chenjing Zhao¹, Jinfei Dai¹, Hua Dong¹, Bo Jiao¹, Xuguang Lan², Zhaoxin Wu^{1

3}

Affiliations

¹ Key Laboratory for Physical Electronics and Devices of the Ministry of Education and Shaanxi Key Lab of Information Photonic Technique, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, China.
² Institute of Artificial Intelligence and Robotics, Xi'an Jiaotong University, Xi'an, China.
³ Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, China.

Abstract

Recently, perovskite light-emitting diodes (PeLEDs) have drew widespread attention due to their high efficiencies. However, because of the sensitivity to moisture and oxygen, perovskite luminescent layers are usually prepared in high-purity nitrogen environment, which increases the cost and process complexity of device preparation and seriously hindrances its commercialization of PeLED in lighting and display application. Herein, dual-phase all-inorganic composite CsPbBr₃-Cs₄PbBr₆ films are fabricated from CsBr-rich perovskite solutions by a simple one-step spin-coating method in the air with high humidity. Compared with the pure CsPbBr₃ film, the composite CsPbBr₃-Cs₄PbBr₆ film has much stronger photoluminescence emission and longer fluorescence lifetime, accompanied by increased photoluminescence quantum yield (33%). As a result, we obtained green PeLED devices without hole transport layer exhibiting a maximum brightness of 72,082 cd/m² and a maximum external quantum efficiency of about 2.45%, respectively. More importantly, the champion device shows excellent stability with operational half-lifetime exceeding 1,000 min under continuous operation in the air. The dual-phase all-inorganic composite CsPbBr₃-Cs₄PbBr₆ film shows attractive prospect for advanced light emission applications.

Keywords: CsPbBr3-Cs4PbBr6 composites; all-inorganic perovskites; device stability; dual-phase; perovskite light-emitting diodes.