The synthesis and characterization of a hexanuclear copper–yttrium complex for deposition of semiconducting CuYO2–0.5Cu2O composite thin films

The copper–yttrium hexanuclear complex [Cu4Y2(dmae)6(OAc)7.85(OH)0.15(H2O)2]·2CH3C6H5 (1) (where dmae = dimethylaminoethanoato, OAc = acetato) has been synthesized and characterized by its melting point, elemental analysis, and FT-IR, thermogravimetric/differential thermogravimetric (TG/DTG) and single crystal X-ray diffraction analyses. The complex crystallizes in the triclinic space group P with cell parameters a = 9.4934(3) A, b = 13.2045(4) A, c = 14.6990(5) A, α = 76.486(2)°, β = 85.811(2)° and γ = 83.394(2)°. A thin film of a CuYO2–0.5Cu2O composite has been deposited on a FTO glass substrate by implementation of the complex (1) at 400 °C under an argon atmosphere via aerosol assisted chemical vapour deposition (AACVD). XRPD, SEM and EDX analyses reveal the formation of impurity-free crystalline mixtures of the CuYO2–0.5Cu2O composite with well-defined evenly distributed rods of Cu2O in the size range of 0.85–1.05 μm and granules of CuYO2 in the size range of 110–125 nm. UV-Vis spectrophotometric measurements and photoelectrochemical (PEC) results show an optical band gap energy of 2.6 eV and a photocurrent density of 81 μA cm−2 under illumination using a 150 W halogen lamp at a potential of 1.0 V vs. SCE.