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We report Eu3+, Sm3+ co-doped La(OH)3 nano-crystalline red emitting phosphor prepared following combustion synthesis protocol. The structural and morphological information about the synthesized samples have been explored using X-ray diffraction (XRD) and transmission electron microscopic (TEM) techniques. The optical properties of the samples have been investigated under 355 nm laser excitations. The sample emits intense red emissions at 625 and 707 nm due to 5D0 → 7F2 and 5D0 → 7F4 transitions in Eu3+ ion, respectively. The concentrations of both, Eu3+ and Sm3+ in the samples were optimized at 1 mol% to get maximum fluorescence. The presence of Sm3+ in the Eu3+ doped sample enhances the emission intensity up to two times. The samples annealed at higher temperature show significant enhancement in the emission intensity. The life time studies show an efficient energy transfer from Sm3+ to Eu3+ ions and have been discussed with the help of schematic energy level diagram. This enhancement in the emission intensity is discussed in terms of the rare earth ion concentration, annealing temperature and energy transfer. [ABSTRACT FROM AUTHOR]

Highlights: [•] Er3+ doped and Er3+/Ce3+ co-doped silica–germanate glasses are fabricated. [•] The thermal stability and spectra properties are investigated. [•] The FWHM of Er3+/Ce3+-codoped silica–germanate glass reaches 108nm. [•] The stimulated emission cross-sections are calculated and discussed. [•] The gain spectra of prepared samples are also investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] Er3+/Er3+–Yb3+ doped/codoped TeO2–ZnO (TZO) glasses have been fabricated by the melting and quenching method. [•] Upconversion emission has been investigated using 976nm excitation. [•] The mechanisms responsible for the observed upconversion emissions in the doped/codoped samples have been explained. [•] Judd–Ofelt theory has been applied. [ABSTRACT FROM AUTHOR]