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Updated: Feb 1, 2026
Microfluidic Pneumatic Cages: A Novel Approach for In-chip Crystal Trapping, Manipulation and Controlled Chemical Treatment
Published on: July 12, 2016
Crystal field modulation-control, bandgap engineering and shallow/deep traps tailoring-guided design of a
Weixin Zheng1, Haoyi Wu, Guifang Ju
1School of Physics and Optoelectronic Engineering, Guangdong University of Technology, WaiHuan Xi Road, No. 100, Guangzhou 510006, China. yhjin@gdut.edu.cn.
Abstract:
In this paper, a new color tunable long persistent phosphor (Ca, Sr)Ga4O7:Mn2+,Bi3+ has been successfully synthesized via a high-temperature solid-state reaction. Crystal field modulation and band gap engineering controlled by Sr2+ substitution for Ca2+ realizes the color tunable Mn2+ emission from 580 to 556 nm. Guided by the tailoring of traps distribution, the long persistence luminescence (LPL) performance of CaGa4O7:Mn2+ is greatly enhanced to 33 times higher brightness and much longer persistent time through Bi3+ co-doping. Furthermore, aided by the Rietveld refinement method, steady/transient-state fluorescence and thermoluminescence (TL) techniques with the combination of DFT calculations, the crystal structure evolution, electronic structure, trap distribution tailoring, self reduction of Mn4+, and the related color tunable Mn2+ photoluminescence/enhanced LPL properties are systematically characterized. Finally, a schematic diagram is proposed for a detailed illustration of the photoluminescence and LPL mechanisms.
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