The structural and luminescent properties of Lu_3Al_5O_(12):Ce~(3+) + Lu_2O_3 crystal phosphors prepared by colloid chemical synthesis

摘要

The crystal structure and spectral luminescent properties of composite phosphors Lu_3Al_5O_(12):Ce~(3+) + Lu_2O_3 synthesised by colloid chemical approach have been studied by means of X-ray and neutron powder diffraction and optical spectroscopy methods. The formation of stable defect structures on the phase boundary between Lu_3Al_5O_(12):Ce~(3+) and Lu_2O_3 evidenced. A redistribution of optically active Ce~(3+) ions between initial Lu_3Al_5O_(12) and lutetium oxide Lu_2O_3 phase occurs during the colloid chemical synthesis, resulting in suppression of luminescence intensity. The modification of luminescent properties by Lu_2O_3 doping in Lu_3Al_5O_(12):Ce~(3+)+ Lu_2O_3 is drastically different in comparison with Y_3Al_5O_(12):Ce~(3+) + Lu_2O_3. The chemical and structural mechanisms of Lu_2O_3 doping effects on luminescence properties of lutetium and yttrium garnet-based compounds are discussed.