Size dependent luminescence of nanocrystalline Y sub(2)O sub(3):Eu and connection to temperature stimulus

In the emission spectra of nanocrystalline Y sub(2)O sub(3):Eu with decreasing the particle size, the super(5)D sub(0)- super(7)F sub(0) transition of Eu super(3+) shifts towards blue. This size effect is explained by lattice expansion of the nanocrystallines, more precisely, by larger Eu-O distance. Meanwhile, increasing temperature also expands the lattice constant and shifts the emission peak to blue. Then nephelauxetic effect is employed to organize the size effect and temperature dependence. It is also introduced to indicate the change of Eu super(3+) coordination number in the nanosized phosphor. Based on the experimental results, possible applications of temperature sensing and stress mapping with Eu super(3+) doped nanocrystalline phosphors are proposed.