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Sm3+, Tb3+ co-doped SrSnO3 perovskites were successfully prepared by the sonochemical method and solid-state reactions. X-ray diffraction showed well-defined peak characteristics of the SrSnO3 orthorhombic phase, while SEM analysis revealed the formation of rod-like structures composed of particles with a mean size of 100 nm. Under the excitation of 325 nm, the photoluminescence spectra exhibited a broad emission band (380–500 nm) related to intrinsic defects and peaks attributed to characteristic electronic transitions of Tb3+ (5D4→7F6, 489 nm, 5D4→7F5, 542 nm) and Sm3+ (4G5/2→6H5/2, 570 nm, 4G5/2→6H7/2, 605 nm) ions. Through co-doping with these rare earths, the emission from perovskite can be tuned. The obtained chromaticity coordinates are (0.33, 0.31) and (0.34, 0.32) for 4Sm2Tb and 4Sm4Tb perovskites, respectively. It indicates the promising application potential of Sm3+, Tb3+ co-doped SrSnO3 as single-phase perovskite for UV excited white light-diodes.

Silica-coated cadmium telluride quantum dots (CdTe@SiO2) exhibit increased sensitivity to UV illumination within the 300–400 nm range, allowing long and efficient Stokes-shifted emissions with more than 300 nm of separation from the excitation source. In addition, the surface modification of water-soluble CdTe quantum dots promotes a better dispersibility in a non-polar solvent (chloroform), allowing the facile fabrication of a highly luminescent PMMA/CdTe@SiO2 composite with uniformly distributed CdTe@SiO2 clusters suitable for photonic applications.