Gd 2 O 3 :Yb 3+ phosphor has been synthesized by the solid state reaction method with boric acid used as a flux. The resulting Gd 2 O 3 :Yb 3+ phosphor was characterized by X-ray diffraction (XRD) technique, Fourier transmission infrared spectroscopy (FTIR), scanning electron microscope (SEM) and transmission electron microscope (TEM), and photoluminescence and thermoluminescence. The results of the XRD show that obtained Gd 2 O 3 :Yb 3+ phosphor has a cubic structure. The average crystallite sizes could be calculated as 42.9 nm, confirmed by the TEM results. The study suggested that Yb 3+ doped phosphors are potential luminescence material for IR laser diode pumping.
A europium (Eu)-doped di-calcium magnesium di-silicate phosphor, Ca2MgSi2O7 :Eu(2+) , was prepared using a solid-state reaction method. The phase structure, particle size, surface morphology, elemental analysis, different stretching mode and luminescence properties were analyzed by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) and mechanoluminescence (ML). The phase structure of Ca2MgSi2O7:Eu(2+) was an akermanite-type structure, which belongs to the tetragonal crystallography with space group P4̅21 m; this structure is a member of the melilite group and forms a layered compound. The surface of the prepared phosphor was not found to be uniform and particle distribution was in the nanometer range. EDX and FTIR confirm the components of Eu(2+)-doped Ca2MgSi2O7 phosphor. Under UV excitation, the main emission peak appeared at 530 nm, belonging to the broad emission ascribed to the 4f(6) 5d(1) → 4f(7) transition of Eu(2+). The ML intensity of the prepared phosphor increased linearly with increasing impact velocity. A CIE color chromaticity diagram and ML spectrum confirmed that the prepared Ca2MgSi2O7:Eu(2+) phosphor would emit green color and the ML spectrum was similar to that of PL, which indicated that ML is emitted from the same center of Eu(2+) ions.
Sr2MgSi2O7:Eu(2+) and Sr2MgSi2O7:Eu(2+),Dy(3+) long afterglow phosphors were synthesized under a weak reducing atmosphere by the traditional high temperature solid state reaction method. The synthesized phosphors were characterized by powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and photo-, thermo- and mechanoluminescence spectroscopic techniques. The phase structure of the sintered phosphor was an akermanite type structure, which belongs to tetragonal crystallography. The thermoluminescence properties of these phosphors were investigated and compared. Under ultraviolet light excitation, the emission spectra of both prepared phosphors were composed of a broad emission band peaking at 470 nm. When the Sr2MgSi2O7:Eu(2+) phosphor was co-doped with Dy(3+), the photoluminescence (PL), afterglow and mechanoluminescence (ML) intensity were strongly enhanced. The decay graph indicated that both the sintered phosphors contained fast decay and slow decay processes. The ML intensities of Sr2MgSi2O7:Eu(2+) and Sr2MgSi2O7:Eu(2+),Dy(3+) phosphors were increased proportionally with increasing impact velocity, a finding that suggests that these phosphors could be used as sensors to detect the stress of an object.
A series of rare earth doped and co-doped distrontium magnesium di-silicate phosphors namely: Sr 2 MgSi 2 O 7 :Ce 3? , Sr 2 MgSi 2 O 7 :Eu 2? and Sr 2 MgSi 2 O 7 :Eu 2? , Ce 3? were prepared by the solid state reaction method. The crystal structures of sintered phosphors were an akermanite type structure which belongs to the tetragonal crystallography. The chemical compositions of sintered phosphors were confirmed by energy dispersive X-ray spectroscopy (EDS). Under the ultraviolet excitation, the emission spectra of both Sr 2 MgSi 2 O 7 :Eu 2? and Sr 2 MgSi 2 O 7 :Eu 2? , Ce 3? phosphors were composed of a broad band peaking at 460 nm, belonging to the broad emission band. When the Sr 2 MgSi 2 O 7 :Eu 2? phosphor is co-doped with Ce 3? ions, thermouminescence, photoluminescence, afterglow and mechanoluminescence (ML) intensity were strongly enhanced. The Sr 2 MgSi 2 O 7 :Eu 2? phosphor showed some afterglow with short persistence time. Ce 3? phosphors were proportionally increased with the increase of impact velocity, which suggests that these phosphors can be used as sensors to detect the stress of an object. Thus the present investigation indicates that the piezoelectricity is responsible to produce ML in prepared phosphors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.