COMPOSITION CONTAINING A CORE-SHELL ALUMINATE, PHOSPHOR OBTAINED FROM SAID COMPOSITION, AND PREPARATION METHODS

摘要

A composition comprising an inorganic core and an aluminate shell is described. The aluminate can have the formula (1): (CeaTbb)Mg1+xAl11+yO19+x+y (1), where a, b, x and y comply with the relations a+b=1-0.2@x@+0.2 and -0.2@y@+0.2, wherein the shell uniformly covers the inorganic core over a thickness of no less than 300 nm. A phosphor is also described that can be obtained by calcinating the composition at a temperature of at least 1200° C.