Influence of grain size on luminescence properties of micro- and nanopowder Zn₂V₂O₇ vanadate

Micro- and spongiform nanocrystalline Zn₂V₂O₇ compounds were synthesized by hydrothermal and solid-state reaction techniques, and their morphological features were investigated by scanning electron microscopy (SEM). The grain size ranges of the produced powders were 3–15, 0.5–2 μm, and 50–500 nm. The luminescence spectra of these compounds were measured under pulse cathode beam and photoexcitation (200–400 nm). The luminescence decay properties of Zn₂V₂O₇ were studied. It is found that the intensity, maximum position of luminescence spectra and luminescence decay time of Zn₂V₂O₇ samples depend considerably on the grain size of the synthesized powders. The processes of energy relaxation in Zn₂V₂O₇ and the observed size effect on the luminescence properties are also discussed. - Highlights: • Spongiform nanocrystalline α-Zn₂V₂O₇ was synthesized. • Grain size of α-Zn₂V₂O₇ influence its luminescence properties. • The lattice parameters of α-Zn₂V₂O₇ depend on the grain size in submicron range.