LaBO:xDy (x = 0.05 mol%, 0.1 mol%, 0.2 mol%, 0.5 mol%, 1 mol% and 2 mol%) phosphors were synthesized by solid-state reaction method. X-ray diffraction technique was used to confirm the formation of compound. Photoluminescence emission spectra shows two emission peaks at 470 nm and 575 nm when excitation wavelength is set at 352 nm. Photoluminescence intensity increases upto 1 mol % of Dy and then starts decreasing. Dipole-dipole interaction is found to be responsible for concentration quenching of photoluminescence intensity. Commission Internationale de I'Eclairage (CIE) chromaticity diagram demonstrates that the phosphor emits in bluish white region of the visible spectrum. Critical energy transfer distance between dopant ions was determined. The mechanoluminescence characteristics were studied by the impact method. The peaks of both the mechanoluminescence (ML) intensity and the total ML intensity of the UV exposed phosphors increases with increasing impact velocity for 1 mol % concentration of Dy. The ML sensitivity of the LaBO:Dy (Dy = 1 mol %) phosphor is comparable with the reported ML of various inorganic phosphors. The thermoluminescence characteristics of the samples were also investigated. Thermoluminescence glow peaks were recorded with 480 Gy, 80 Gy and 20 Gy dose of γ-irradiation from Co Source. TL trapping parameters were determined by Chen's peak shape method and glow curve deconvolution method. LaBO:Dy phosphors were found to be good mechanoluminescent materials and can be used in stress sensing application.

Li6Y(BO3)3 phosphor was prepared using solid‐state synthesis by varying europium/dysprosium (Eu/Dy) concentrations in the range 0.05–1.0 mol%. X‐ray diffraction and Fourier transform infrared characterizations provided insight into the phase, crystallinity, morphology and functional groups. Photoluminescence (PL) of the Li6Y(BO3)3:Dy3+ phosphor was also studied. Li6Y(BO3)3:Dy3+ displayed excellent PL due to the characteristic emission of Dy3+ ions in the visible region at 482 nm (4F9/2→6H15/2) and 580 nm (4F9/2→6H13/2,), when excited at 352 nm. The Li6Y(BO3)3:Eu3+ phosphor was discussed in our previous publication. Uniaxial compression experiments on Li6Y(BO3)3 showed that the mechanoluminescence (ML) intensity was linearly dependent on mechanical power. When pressure was applied to these phosphors mixed in an epoxy resin, initially the ML intensity increased with time, attained a peak value Im at a particular time tm, and decreased further with increase in time. After tm, ML intensity decreased exponentially, initially at a faster rate that subsequently slowed down, ML intensity increased linearly for a wide measurement range of dynamic load that made the Li6Y(BO3)3 phosphor a good elastico ML (EML) material to be utilized as a stress sensor with Li6Y(BO3)3:Eu3+ and showing greater ML intensity than Li6Y(BO3)3:Dy3+.

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