Studies On Preparation Of Nanostructure ZrO₂/SiO₂, Self-assembly Mechanism And Catalytic Activity Of Its Superacid Catalyst

Nano-Zirconium oxide, or nano-zirconia, owning many special properties, is largely used in fire-resistant material and ceramic pigment material and it also have been paid more attention to the application of special ceramic, energy, environment, material and so on. Especially, of late,optics-glass, zirconia fiber and catalyst hold great promise in many fields.In this paper using sol-gel technology and self-assembly method, ZrOCl₂ as the raw material, 12 alkyl sodium sulphate (C₁2H₂4SO₄Na) aqueous solution as organic self-assembly medium, We have successfully assembled different layers, contents and surface structures nano-zirconia on the SiO₂ small ball which approximate diameter is 1.0 mm. The experimental conditions and the mechanism are also studied. After treated by H₂SO₄ solution, the novel superacid catalyst is prepared and its catalysis capability is also discussed.The studies are as follows:1. Using sol-gel technology and layer by layer self-assembly method, ZrOCl₂ and CH₃COOH as raw material, 12 alkyl sodium sulphate (C₁2H₂4SO₄Na) aqueous solution as organic self-assembly medium, we have successfully prepared different layers, contents and surface structural nanometer ZrO₂ on the SiO₂ small ball. The influence of different experimental conditions on the preparation is studied.2. 12 alkyl sodium sulphate (C₁2H₂4SO₄Na) aqueous solution serving as self-assembly medium, we investigate the mechanism of self-assembly by determining the absorption isotherm, Zeta potential, contact angle, and spectrum of IR. It shows that SiO₂ covers negative electricity on its surface, so it can form a single absorption layer with Zirconium sol. By means of the absoiption of the organic chain of two C₁2H₂4SO₄Na molecules then it will be a double-molecule-layer absorption and form a half-micelle absorption. In this structure the polar group is towards outside so it carries negative electricity on the surface and it can absorb the particle in the sol which carries positive electricity. In this way the nanometer particle ZrO₂ can be assembled on the surface of SiO₂ The mechanism of self-assembly will give a direction for the study of optimizing the preparation conditions and control the reaction process.3. All of the samples have been characterized by XRD, SEM, X-ray energy spectrum, IR, TG-DTA , etc. The results show that: (1)The self-assembly medium can influence the microenvironment of the carrier surface and the absorption content of the carrier surface. The absorption state of the carrier surface can be controlled by altering the self-assembly medium concentration and the alternation also lead to change the electric property of the carrier...