The interface and surface acidity of heterogeneous catalysts are widely applied to manipulate the catalytic performance. However, the interface structure prepared by traditional synthesis processes required multistep procedures, which was still lack of controllability and stability. Here, we show a general synthetic approach to fabricate ultra-stable heterogeneous catalysts with tailored molecular interfacial structure and super acidity in one step. The as-synthesized SiW 12 O x /TiO 2 catalyst was used for photo-catalytic conversion of methane to value-added oxygenates. We propose that the formed molecular interface W 12 À OHÀ Ti coupled with the introduced Brønsted acid sites of POMs, results in enhancing the photocatalytic performance. Namely, the addition of SiW 12 O x can reduce the recombination of electrons and holes for triggering charge separation owing to the photoelectron capturing by proton, improving electron transfer to reactants and thereby promoting catalytic activity. This fabrication method provides a way to build molecular interface photo-catalyst by POMs with super acidity and ultrastable structure.

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The effective conversion of carbon dioxide (CO2) into high value-added carbon-containing chemicals or liquid fuels in mild condition is greatly significant for reducing air pollution and supplementing carbon-containing energy shortages. Polyoxometalates (POMs) possess semiconductor-like properties, reversible redox properties, and structural stability, which represent a class of good electron acceptors that can effectively enhance the photocatalytic performance of semiconductor catalysts. This paper discusses an innovatively designed comprehensive experiment based on scientific research results. The CrMo6/TiO2 photocatalyst was prepared by loading Anderson type POMs, such as CrMo6 on TiO2, by the impregnation method. The material structure was analyzed by means of Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV-Vis diffuse reflectance. The research results showed that CrMo6/TiO2 can efficiently convert carbon dioxide into formic acid et al. liquid products. Anderson type POMs modification of TiO2 can reduce the energy band gap and the energy required for photocatalysis. This experiment combines inorganic chemistry, physical chemistry, materials chemistry, 大 学 化 学Vol. 38 organic chemistry, analytical chemistry, and other basic chemistry courses, popularizes the concepts of synthetic chemistry and green chemistry, and improves students' environmental awareness, innovation ability, and comprehensive ability.