Study On The Preparation Technonlogy Of Nano Fe₃O₄ And CuO And Their Synergistic Enhancement And Catalytic Application

Nanoparticles have a variety of excellent properties and nano effects, while the nano effect of metal oxide is prominent in the synergistic and catalytic effect. In this paper, the synergistic enhancement effect of nano Fe₃O₄ on siliver nanoparticles in SERS was investigated, and the catalytic effect of nano CuO on the explosive combustion process was also researched.By utilizing of solvothermal, forced hydrolysis and double oxidation progress, Fe₃O₄ nanoparticles, CuO nanoparticles and GO were prepared respectively. As the objiect to be coordinated, the traditional and the modified silver sol with SERS activity were prepared by the traditional Lee method and its modifition. UV-Vis, XRD and TEM technologies were applied to characterize the simples.1. Synergetic enhancement effect:A series of Ag-Fe₃O₄/GO （1:x） composite substrates were obtained by using a one-pot method to load the different proportion of Ag nanoparticles and Fe₃O₄ nanoparticles on the bearing platform grapheme oxide（GO） through salt regulation method. By means of two step method, the Fe₃O₄/GO-Ag（1:x） composite substrates were preparated. Raman spectrometer was applied to evaluate the SERS performances of these substrates in detecting the 4-Mpy with 10-6M. The results showed that the addition of Fe₃O₄ could significantly improve the SERS performance of the substrates, and there was a synergistic enhancement effect for Fe₃O₄ to Ag nanaoparticles when detecting the SERS signal. The different synergetic effect was obtained due to the different surface state of nano Fe₃O₄. The better synergetic effect could be obtained in the good water solubility of Fe₃O₄ with a lot of carboxyl groups on the surface. Compared with one-pot, the two step method makes the contact between Ag and Fe₃O₄ more fully, and the SERS performance of the substrate is higher.2. Catalytic combustion effect:The flame propagation velocity of the fule air explosive （FAE） play a very importmant role in its expolsive power. Taking lycopodium powder as the experimental object, a dust explosion flame propagation test system was used to simulate the explosion progress of FAE. The effects of CuO on the flame propagation velocity of dust esplosion were studied by the addition of 1%,3% and 5% CuO nanoparticles. The results showed that the dust flame burning can be catalyzed by after the addition of CuO, and the top speed of flame propagation can be improved. For the dust concentration of 250 g/m3 and 500 g/m3, the maximum of flame propagation can be obtained when the addition content of CuO is 3%. While for the dust concentration of 250 g/m3 and 500 g/m3, the optimum addition content of CuO is 5%. The nano CuO has a good catalytic combustion effect on the combustible materials in cloud state distribustion, providing a useful research idea to improve the power of the FAE.