We investigated the growth and properties of CuAlO2 single crystals grown by a flux self-removal method. In this method, the flux crept up the wall of an alumina crucible completely during the slow cooling process, leaving flux-free CuAlO2 crystals on the bottom of the crucible. The resulting CuAlO2 crystals had typical dimensions of 0.5-5 mm in the ab-plane and 10-300 mm along the c-axis. The crystals had a hexagonal structure with a=b=2.857(1) Å and c=16.939(2) Å. Their resistivity was anisotropic with a c-axis resistivity (ρc) about ∼17 times higher than the ab-plane resistivity (ρab). However, both ρab and ρc showed thermally activated behavior with the same activation energy of ∼0.6 eV. The CuAlO2 crystals had direct and indirect bandgaps of 3.40 eV and 2.22 eV, respectively.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Inorganic Chemistry
- Materials Chemistry