Inorganic salt recrystallization strategy for achieving ultralong room temperature phosphorescence through structural confinement and aluminized reconstruction

Li Ya Liang; Bin Bin Chen; Yue Wang; Ya Ting Gao; Shuai Chang; Meng Li Liu; Da Wei Li

doi:10.1016/j.jcis.2023.06.089

Inorganic salt recrystallization strategy for achieving ultralong room temperature phosphorescence through structural confinement and aluminized reconstruction

J Colloid Interface Sci. 2023 Nov:649:445-455. doi: 10.1016/j.jcis.2023.06.089. Epub 2023 Jun 18.

Authors

Li Ya Liang¹, Bin Bin Chen², Yue Wang¹, Ya Ting Gao¹, Shuai Chang¹, Meng Li Liu³, Da Wei Li⁴

Affiliations

¹ Key Laboratory for Advanced Materials, Shanghai Key Laboratory of Functional Materials Chemistry, Frontiers Science Center for Materiobiology & Dynamic Chemistry, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
² Key Laboratory for Advanced Materials, Shanghai Key Laboratory of Functional Materials Chemistry, Frontiers Science Center for Materiobiology & Dynamic Chemistry, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China; School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), 2001 Longxiang Boulevard, Longgang District, Shenzhen City, Guangdong 518172, China. Electronic address: chenbinbin@cuhk.edu.cn.
³ School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), 2001 Longxiang Boulevard, Longgang District, Shenzhen City, Guangdong 518172, China.
⁴ Key Laboratory for Advanced Materials, Shanghai Key Laboratory of Functional Materials Chemistry, Frontiers Science Center for Materiobiology & Dynamic Chemistry, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: daweili@ecust.edu.cn.

PMID: 37354801
DOI: 10.1016/j.jcis.2023.06.089

Abstract

Achieving highly efficient and stable room temperature phosphorescence (RTP) with ultralong lifetime is critical for the multi-purpose applications of phosphorescent materials. In this work, we propose an inorganic salt heating recrystallization strategy to simultaneously improve the lifetime, quantum efficiency, and stability of phosphorescent scandium/leucine microspheres (Sc/Leu-MSs). Inorganic salt-treated Sc/Leu-MSs are obtained by simply heating and drying inorganic salt solution containing Sc/Leu-MSs, which can achieve a maximum lifetime increase of 4.42-times from 208.37 ms (Sc/Leu-MSs) to 920.08 ms (Al₂(SO₄)₃-treated Sc/Leu-MSs), accompanied by a RTP intensity increase up to 24.08-times. The enhancement mechanism of RTP efficiency is attributed to the stabilization of triplet excitons caused by inorganic salt coating that suppresses molecular motion and isolates oxygen on the one hand, and the efficient intersystem crossing promoted by aluminized reconstruction-caused duplex heavy atom effects on the other hand. This study provides new design principle and a facile strategy to construct RTP materials with ultralong lifetime, high phosphorescent quantum efficiency, and high stability for promising applications such as anti-counterfeiting and light emitting diodes.

Keywords: Aluminized reconstruction; Duplex heavy atom effects; Inorganic salt heating recrystallization; Rare earth microsphere; Room temperature phosphorescence; Structural confinement.