The Buliding Of Double Metal Oxide/g-C₃N₄/MOF Composites And Its Photocatalytic

N-K2Ti4O9 and Bi2Fe4O9 were prepared by a high temperature calcining and a solvothermal process, respectively. G-C3N4 was also prepared by the high temperature calcining, and then modification of N-K2Ti4O9 or Bi2Fe4O9 and g-C3N4 can generate electrostatic attraction, and connect them together to produce binary composites, based on which ternary composite can be obtained by coordination reaction of UiO-66. Then the pure materials and the composites were characterized, and their photocatalytic performance under visible light and synergistic mechanism were studied. This dissertation is composed of three parts.(1)N-K2Ti4O9/MIL-101 was successfully synthesized by hydrothermal method and were characterized by powder X-ray diffraction(XRD), field emission transmission electron microscopy(FETEM), thermogravimetric analysis(TG) and N2 adsorption-desorption (BET) and so on. Moreover, the photocatalytic activities of the catalysts were evaluated by measuring the degradation of Rhodamine B under visible light. Meanwhile, the synergistic effect induced by compounding was quantitatively evaluated by the proposed synergistic factor. The results show that the composites exhibit higher photocatalytic activity as compared with the pure materials. The synergistically enhanced photocatalytic activity of the composites is due to big adsorption capacity of MIL-101 and high separation efficiency of photogenerated electron-hole pairs through interfaces between N-K2Ti4O9 and MIL-101.(2) Modification of N-K2Ti4O9 and g-C3N4 by Na2C2O4 and nitric acid, respectively, can generate electrostatic attraction, and connect them together to produce binary composites N-K2Ti4O9/g-C3N4, based on which ternary composite can be obtained by coordination reaction of UiO-66. Photocatalytic activities of the catalysts were investigated by the degradation of RhB under visible light irradiation. The results show that the ternary composites exhibit higher photocatalytic activity as compared with the binary composites and the pure materials. The synergistically enhanced photocatalytic activity of the ternary composites is due to coupling direct solid-state Z-scheme N-K2Ti4O9/g-C3N4 heterojunction with high adsorption capacity of UiO-66 for RhB. Compounding can note only promote the separation of electron-hole pairs, and but also raise the capacities of oxidation and reduction for hole and electron, respectively.(3) The Bi2Fe4O9/g-C3N4/UiO-66 ternary composites were synthesized by a facile solvothermal method. The prepared samples were characterized. Moreover, the photocatalytic activities and stability of the catalysts were evaluated by measuring the degradation of Rhodamine B under visible light and the results show that the ternary composites exhibit higher photocatalytic activity as compared with the binary composites and the pure materials.