X-ray absorption spectroscopy and neutron-diffraction study of persistent luminescent Sr2MgSi2O7 glass-ceramics

Glass-ceramics based on the Eu2O3/Dy2O3-doped Sr2MgSi2O7 phosphor have been obtained from sintering and crystallization of glass powders. The doped parent glasses show red emission under excitation UV light. After thermal treatment, corresponding glass-ceramics persistent blue which emanates Eu2+ incorporated in crystals; also occurs Eu3+ residual vitreous phase. aim this work is to investigate structure defects such as oxygen strontium vacancies crystals environment, oxidation state coordination Eu Dy ions glass-ceramics, their partitioning between crystalline glassy phase influence luminescence properties, employing X-ray absorption spectroscopy (XAS) neutron diffraction (ND) investigative structural tools. We suggest that mechanism involves presence shallow electron traps are abruptly emptied for temperatures above 100 K. most likely due an effective concentration dendritic-shaped one particular compositions, with a suitable level Sr vacancies, even though formed all investigated samples.