Novel photoluminescent properties of LiGaO2 nanoflakes

The luminescence properties of LiGaO2 microflakes synthesized using the sol–gel process are investigated. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) and absorption spectra. The PL spectra excited at 325 nm have a broad and strong emission band with a peak at 383 nm, which corresponds to the self-activated luminescence of the tetrahedral gallium group. The optical absorption spectra of the sample annealed at 600 °C exhibited a band-gap energy of 3.38 eV.

► We investigated the well-crystallized orthorhombic LiGaO2 obtained by heat-treatment above 500 °C.
► The excitation wavelengths at about 325 nm, were associated with charge transfer between Ga and O with Ga3+ ions in tetrahedral co-ordination.
► The PL spectra under 325 nm excitation showed a broad and strong emission peaks at about 383 nm, was originated from the tetrahedral gallium group.
► The absorption edge of 600 °C sample was at 367 nm, which corresponded to a band-gap energy of 3.38 eV.