Dysprosium doped di-strontium magnesium di-silicate white light emitting phosphor by solid state reaction method

Abstract

Dysprosium doped di-strontium magnesium di-silicate namely Sr2MgSi2O7:Dy3+ phosphor was prepared by the solid state reaction method. The phase structure, surface morphology, particle size, elemental analysis was analyzed by using XRD, TEM, EDX and FTIR techniques. The EDX and FTIR spectra confirm the present elements in Sr2MgSi2O7:Dy3+ phosphor. The optical properties of Sr2MgSi2O7:Dy3+ phosphor was investigated utilizing thermoluminescence (TL), photoluminescence (PL), long lasting phosphorescence and mechanoluminescence (ML). Under the ultraviolet excitation, the emission spectra of Sr2MgSi2O7:Dy3+ phosphor are composed of a broad band and the characteristic emission of Dy3+ peaking at 470nm (blue), 575nm (yellow) and 678nm (red), originating from the transitions of 4F9/2→6H15/2, 4F9/2→6H13/2 and 4F9/2→6H11/2. CIE color coordinates of Sr2MgSi2O7:Dy3+ are suitable as white light emitting phosphor. Decay graph indicate that this phosphor also contains fast decay and slow decay process. The peak of ML intensity increases linearly with increasing impact velocity of the moving piston. The possible mechanism of this white light emitting long lasting phosphor is also investigated.