Preparation And Properties Investigation Of Spinel Zinc Ferrite Nanoparticles

Spinel zinc ferrite was widely used in gas-sensitive sensors, catalyst, for its good gas-sensitive and characteristics photocatalytic activity. In this paper, with nitrate solution as raw materials, spinel ZnFe₂O₄ nanoparticles were prepared by sol-gel and carbon adsorption. The main contents and conclusions were as follows:Spinel ZnFe₂O₄ nanoparticles were preared by a modified sol-gel route.In this route, the solution was better gelled by using acrylamide, simultaneously an appropriate amount of glucose was added to prevent the gel shrinkage during drying. The results showed that high-phase-purrity ZnFe₂O₄ nanoparticles can be prepared by using the chelating agent citric acid, ethylenediamine-tetraacetic acid (EDTA) and ethylenediamine-tetraacetic acid (EDTA) at a sintering temperature of 500℃. Using different chelating agent had influence on the grain size and morphology of ZnFe₂O₄ nanoparticles. By using citric acid as chelating agent the ZnFe₂O₄ nanoparticles have a good dispersion; the ZnFe₂O₄ nanoparticles by using ethylenediamine-tetraacetic acid (EDTA) as chelating agent has a certain effect on grain refinement, but with a certain degree of adhension phenomenon.Carbon adsorption is a new route to the preparation of nanoparticles, which is used the strong adsorption property of activated carbon. We analyzed the parameters, which included the amount of activated carbon, the pH value of solution, the sintering temperature to the influence of ZnFe₂O₄ nanoparticles.The results revealed that high-phase-purrity ZnFe₂O₄ nanoparticles can be prepared by carbon adsorption, the best parameters for carbon adsorption was: the molar ratio of activated carbon to metal atoms is 2:1, the solution pH value for 3, the sintering temperature for 500℃.Analysed and compared the morphology and magnetic of ZnFe₂O₄ nanoparticles prepared by sol-gel and carbon adsorption .The result revealed that high-phase-purrity ZnFe₂O₄ nanoparticles can be prepared by using two methods at the sintering temperature for 500℃.The ZnFe₂O₄ nanoparticles prepared by sol-gel and carbon adsorption have a smaller grain size and a good dispersion. The VSM showed the ZnFe₂O₄ nanoparticles displayed paramagnetic at room temperature.The hysteresis loop of ZnFe₂O₄ nanoparticles preparaed by carbon adsorption displayed an obvious "S" shape, explained that ZnFe₂O₄ nanoparticles prepared by carbon adsorptionwith a smaller size.