LAUSR

Abstract In this work, Bi1-xPrxGeSbO6 (x = 0–0.5) solid solutions were synthesized, and the corresponding properties were compared to those of La1-xPrxGa0.5Sb1·5O6. The lattice parameters of the La1-xPrxGa0.5Sb1·5O6 solid solutions decrease linearly as the activator concentration increases. This linear reduction is only observed for the a parameter for Bi1-xPrxGeSbO6. Parameter c shows non-linear growth, which is related to the structural features of BiGeSbO6. Increasing the activator content leads to a decrease in the particle size, which is 0.5–8 μm for Bi1-xPrxGeSbO6. The influence of the host composition on the spectral-luminescent properties of the solid solutions was determined. The difference in the phonon frequencies of BiGeSbO6 and LaGa0.5Sb1·5O6 leads to different luminescence quenching processes for Pr3+ ions. Interactions between Pr3+ ions and Bi3+ were observed for Bi1-xPrxGeSbO6 solid solutions. These processes give rise to changes in the ratios of the luminescence bands of these ions. All the bismuth-containing solid solutions are characterized by the appearance of an additional band in the spectrum related to the luminescence of the bismuth centres of the BiGeSbO6 host. An evaluation of the colour coordinates (CIE 1931) of the Bi1-xPrxGeSbO6 luminescence showed that the colour of the radiation depends on the praseodymium content: as the praseodymium content increases, the luminescence changes from orange (x = 0.005, 0.01) to yellow-green (x = 0.05–0.5). Broadband thermal emission is observed for Bi0.5Pr0.5GeSbO6 under laser excitation with λ = 457 nm and a power density of J = 6 kW/cm2.