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Using citric acid (C6H8O7·H2O), samarium nitrate (Sm(NO3)3·6H2O) and cobalt nitrate (Co(NO3)3·6H2O) as main raw materials, the SmCoO3 samples were successfully prepared by sol-gel method. The prepared samples were characterized by thermogravimetry and differential scanning calorimetry (TG-DSC), X-ray diffractometer (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR). Using azo dye methyl orange solution as the simulated sewage, the photocatalytic activity of SmCoO3 samples was explored at different synthesis temperatures and illumination times. The experimental results show that pure SmCoO3 samples can be prepared at a calcination temperature of 600 °C to 1000 °C. Under ultraviolet light conditions, the sample of SmCoO3 calcined at 800 °C has the best photocatalytic activity. When illumination times is 120 min, the degradation rate of methyl orange of 10 mg/L can reach more than 97%, and SmCoO3 shows good photocatalytic performance. [ABSTRACT FROM AUTHOR]

Using poly (ethylene oxide)-poly (propylene oxide)- poly (ethylene oxide) (P123), tetraethyl silicon (TEOS), HCl, n-butanol as raw materials, SBA-15 template was prepared by liquid phase reaction method. Using SBA-15 as template, Cu(NO3)2·3H2O and Co(NO3)2·6H2O as raw materials and n-hexane as solvent, mesoporous CuCo2O4 composite metal oxide was prepared by hard template nano-casting. The composite metal oxides were characterized by thermo gravimetric differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Taking benzyl alcohol as the target, the effects of reaction temperature, different catalyst dosage, reaction time and molar ratio of benzyl alcohol to hydrogen peroxide on selective oxidation of benzyl alcohol by CuCo2O4 were studied, and the oxidation products were analyzed by high performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR). The results show that the sample of CuCo2O4 metal composite calcined at 700 °C has the highest purity, and the average particle size is about 500 nm. The optimum conditions for selective oxidation of benzyl alcohol by CuCo2O4 are reaction system temperature of 80 °C, catalyst dosage of 8 g/L, reaction time 3h, the molar ratio 1:1 of hydrogen peroxide to benzyl alcohol. Under the optimum condition, the conversion rate of benzyl alcohol is 78.13% and the recovery rate of benzaldehyde is 56%. Mesoporous CuCo2O4 is a composite metal oxide with good selective oxidation of benzyl alcohol, which has a wide application prospect. [ABSTRACT FROM AUTHOR]