Metallic-type conducting oxide, Cu6O8In1-xMxCl (M=Ca and Cd) whose In site is substituted by Ca or Cd was synthesized by decomposition of molten salt. The crystal structure and electric conductivity of these compounds were investigated. All the compounds synthesized are isostructural to the original compound, Cu6O8InCl. The limits of substitution were x=0.17 for M=Cd and x=0.20 for Ca. The lattice parameter of Cu6O8In1-xMxCl (M=Ca and Cd) increased with increasing amount of substitution obeying Vegard's rule. The lattice parameters at the limit of substitution were α=0.918 nm for M=Cd and α=0.919 nm for Ca. Crystallite size decreased from 90 nm at x=0.00 to 45 nm at x=0.20 with increasing x. However, lattice strain was constant in the range of x studied. Electric resistivity increased with increasing of x for all the compounds studied and superconductivity was not observed down to 12 K. It suggests that doping of a hole by substitution of a divalent cation to In3+ is not effective in changing the charge of Cu in Cu6O8In1-xMxCl (M= Ca and Cd), which controlls the conductivity of superconducting copper oxides.
All Science Journal Classification (ASJC) codes
- 化学 (全般)