Fluorescence enhancement mechanism in phosphor CaAl 12 O 19 :Mn 4 + modified with alkali-chloride

Micro & nano letters

article

Yanan Li¹  Zunhong Xiao¹  Lizhi Xu¹  Yingping Zou²  Mingchun Guo³ 

[1] School of Chemistry and Materials Science, Guizhou Normal University;School of Chemistry and Chemical Engineering, Central South University;School of Chemistry and Materials Science, University of Science and Technology of China

关键词: calcium compounds;    charge compensation;    combustion synthesis;    doping profiles;    fluorescence;    lithium compounds;    manganese;    phosphors;    potassium compounds;    sodium compounds;    spectral line shift;    surface morphology;    fluorescence enhancement mechanism;    alkali-chlorides;    material preparation;    combustion method;    air atmosphere;    Mn concentration;    luminescence properties;    crystal phases;    surface morphology;    fluorescence intensity;    blue shift;    electron cloud deformation;    doping;    alkali metal ions;    hexagonal phase;    cation radius difference;    luminous centre;    charge compensation;    red phosphor size;    light emitting diode applications;    CaKAl12-xO19Mn4+;    CaNaAl12-xO19Mn4+;    CaLiAl12-xO19Mn4+;   

DOI  :  10.1049/mnl.2012.0809

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

CaMAl 12 − x O 19 : x Mn 4 + (M is one or more of K + , Na + , Li + ) materials were prepared by a combustion method in air atmosphere. The Mn concentration, the influence of one or more alkali-chloride on luminescence properties, crystal phases and surface morphology of the samples were investigated. The fluorescence intensity of CaAl 11.98 O 19 :0.02Mn 4 + modified by combining three kinds of alkali-chloride can be enhanced by three times. Blue shift of CaMAl 12 − x O 19 : x Mn 4 + luminescence is explained from the point of view of enhancing electron cloud deformation after doping. Alkali metal ions were beneficial to form hexagonal CaAl 12 O 19 while there was certain inhibition to other peak strengths. The mechanism is the coexistence of alkali-chloride replacing Al 3 + or Ca 2 + instead of Mn 2 + based on the difference of cation radius, this would increase the luminous centre of Mn 4 + and provide charge compensation at the same time. The size of red phosphors was 5–10 μm, which is useful for light emitting diode applications.

【 授权许可】

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