Morphology-dependent photoluminescence property of red-emitting LnOCl : Eu (Ln = La and Gd)

作者：Lee Seoung Soo; Park Ho In; Joh Chung Hyung; Byeon Song Ho^*

来源：Journal of Solid State Chemistry, 2007, 180(12): 3529-3534.

DOI：10.1016/j.jssc.2007.10.020

• phosphors
• oxychlorides
• solvothermal
• luminescences
• morphology

Three different synthetic methods, the liquid phase process in HCl solution, the solvothermal reaction, and the surfactant-assisted solvothermal reaction, were explored to selectively control the particle shape and to enhance the luminescence intensity of the PbFCl-type red-emitting oxychloride phosphors LnOCl:Eu (Ln = La and Gd). The solvothermal pressure facilitated the low-temperature crystallization of the rod-shape particles for both Ln = La and Gd. It is noted that LaOCl:Eu nanorods show highly porous particle surface and quite low photoemission intensity. In contrast, the solvothermal synthesis could highly enhance the red-emission of GdOCl:Eu with no porous surface so as to be comparable to that of commercial Y2O3:Eu phosphor. An addition of surfactant material during solvothermal reaction yielded a rhomboidal-shape phosphor particles with no porous surface for both Ln = La and Gd. Interestingly, the elimination of surface porosity by using a surfactant significantly increased the emission intensity of LaOCl:Eu. It is proposed that the application of solvothermal technique for the synthesis of the PbFCl-type oxychloride phosphors is very effective to selectively control the particle shape and consequently to enhance the photoemission intensity if we use an appropriate surfactant material.

• 出版日期2007-12