EU~(2+) DOPED CALCIUM CHLOROSILICATE PHOSPHORS: POLYMORPHISM AND LUMINESCENCE PROPERTIES

摘要

In this paper, we discuss synthesis, polymorphism and luminescence properties of Eu~(2+) activated calcium chlorosilicate, (Ca_3SiO_4Cl_2). Two different phases were found, one obtained at 800℃ that shows emission peak at 525nm, and a higher temperature phase obtained at 1000℃ with emission peak at 620 ran. Though the crystal structure of these two phases is very similar, their luminescence showed distinct green and orange emissions under 405nm excitation. Moreover, the thermal stability of these two phases are also distinctly different, low temperature phase was found to be less thermally stable (20% drop at 150℃) compared to the high temperature phase (4% drop at 150℃).