We report a simple method for preparing copper(II) molybdate(CuMoO_4) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing...We report a simple method for preparing copper(II) molybdate(CuMoO_4) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the(CuMo)-precursor gel was studied by thermogravimetry–differential thermal analysis(TG–DTA), Fourier transform infrared spectroscopy(FTIR), and X-ray diffraction(XRD). We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^(2-)] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.展开更多
基金supported by two French-Moroccan projects: Volubilis Partenariat Hubert Curien (PHC No.MA 09 205)Projet de Recherches Convention Internationale du CNRS (CNRS-CNRST No.w22572)
文摘We report a simple method for preparing copper(II) molybdate(CuMoO_4) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the(CuMo)-precursor gel was studied by thermogravimetry–differential thermal analysis(TG–DTA), Fourier transform infrared spectroscopy(FTIR), and X-ray diffraction(XRD). We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^(2-)] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.