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The investigated La1–xRExVO4 (RE = Eu, Sm) solid solutions are characterized by intensive emission of the RE ions that is excited from the wide spectral range including UV region of intrinsic transitions in the vanadate host. We have carried out comparable analysis of characteristics of the La1–xRExVO4 compounds synthesized by three different methods: solid state reaction, co‐precipitation and sol‐gel synthesis. The investigation revealed differences in luminescence and excitation spectra of samples obtained by different methods. Spectra of the samples with lower activator concentrations have a more complicated character. They contain exceed number of lines that is caused by formation of two types of RE3+ emission centers. Spectral exhibitions of the second (“at surface”) type of centers are observed up to x = 0.05, 0.1 and 0.3 for samples synthesized by solid state, co‐precipitation and sol‐gel methods, respectively. The presence of the “at surface” type of centers leads to essential increasing of total intensity of emission. Differences in excitation spectra give us a possibility to suppose that enhancement of luminescence intensity is also due to expanded excitation range caused by “at surface” centers in UV region. Therefore, “at surface” centers satisfy better absorption of UV light. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The La1 − xCaxVO4 and La1 − x − yEuyCaxVO4 (0 ≤ x, y ≤ 0.2) micro/nanosized powders were prepared by aqueous nitrate–citrate sol–gel synthesis. Phase composition of the sample depends on the x and y values. The La0.9Ca0.1VO4 is crystallized in monoclinic structure up to the x = 0.1. The La0.9Eu0.05Ca0.05VO4 sample was also attributed to the monoclinic structure. Increasing concentration of europium and calcium ions in La1 − x − yEuyCaxVO4 solid solutions leads to the change of the crystal structure, and subsequently, stabilization of the tetragonal phase takes place.The obtained samples were characterized by XRD analysis, SEM microscopy, and IR spectroscopy. Luminescence properties of the synthesized powders were studied. Emission of the La1 − xCaxVO4 samples is weak and consists of wide bands in the 450–800 nm spectral range. The observed bands at 570 and 630 were ascribed to electron transitions in the distorted VO4 3− vanadate groups. Emission of the La1 − x − yEuyCaxVO4 samples consists of narrow spectral lines in the 550–730 nm spectral range. The lines are caused by the 5D0 → 7FJ electron transitions in the Eu3+ ions. The Ca2+ ions incorporation increases the intensity of the Eu3+ ions luminescence. Structure of the spectra depends on Ca2+ concentration and excitation wave length. The carried out analysis has revealed that Eu3+ ions form at least two different types of emission centers in the La1 − x − yEuyCaxVO4 samples. The assumption is made that type I centers are formed by the Eu3+ ions in their regular positions in the crystal lattice, while the type II centers have complex structure and consist of Eu3+ ions, Ca2+ cations, and oxygen vacancies.