Preparation of CsPb(Cl/Br)3/TiO2:Eu3+ composites for white light emitting diodes

Chen Zhang; Minqiang Wang; Jindou Shi; Junnan Wang; Zheyuan Da; Yun Zhou; Youlong Xu; Nikolai V Gaponenko; Arshad Saleem Bhatti

doi:10.3389/fchem.2023.1199863

Preparation of CsPb(Cl/Br)₃/TiO₂:Eu³⁺ composites for white light emitting diodes

Front Chem. 2023 May 19:11:1199863. doi: 10.3389/fchem.2023.1199863. eCollection 2023.

Authors

Chen Zhang¹, Minqiang Wang¹, Jindou Shi¹, Junnan Wang¹, Zheyuan Da¹, Yun Zhou¹, Youlong Xu¹, Nikolai V Gaponenko², Arshad Saleem Bhatti³

Affiliations

¹ Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education International Center for Dielectric Research and Shannxi Engineering Research Center of Advanced Energy Materials and Devices, Xi'an Jiaotong University, Xi'an, China.
² Belarusian State University of Informatics and Radioelectronics, Minsk, Belarus.
³ Centre for Micro and Nano Devices, Department of Physics, COMSATS Institute of Information Technology, Islamabad, Pakistan.

Abstract

The inherent single narrow emission peak and fast anion exchange process of cesium lead halide perovskite CsPbX₃ (X = Cl, Br, I) nanocrystals severely limited its application in white light-emitting diodes. Previous studies have shown that composite structures can passivate surface defects of NCs and improve the stability of perovskite materials, but complex post-treatment processes commonly lead to dissolution of NCs. In this study, CsPb(Cl/Br)₃ NCs was in-situ grown in TiO₂ hollow shells doped with Eu³⁺ ions by a modified thermal injection method to prepare CsPb(Cl/Br)₃/TiO₂:Eu³⁺ composites with direct excitation of white light without additional treatment. Among them, the well-crystalline TiO₂ shells acted as both a substrate for the dopant, avoiding the direct doping of Eu³⁺ into the interior of NCs to affect the crystal structure of the perovskite materials, and also as a protection layer to isolate the contact between PL quenching molecules and NCs, which significantly improves the stability. Further, the WLED prepared using the composites had bright white light emission, luminous efficiency of 87.39 lm/W, and long-time operating stability, which provided new options for the development of perovskite devices.

Keywords: CsPb(Cl/Br)3/TiO2:Eu3+; anatase; nano-materials; perovskite; white light emitting diodes.

Grants and funding

This work was supported by the National Natural Science Foundation of China (NSFC, 52161145103 and 61774124), National Key R&D Program of China (2022YFE0122500 and 2019YFB1503200), 111 Program (No. B14040), and Shaanxi Provincial Key Research and Development Program (No. 2021GXLH-Z-084).