Preparation Of Nano-oxides By Solid-state Method At Lower Temperature

Oxides are one kind of very important materials, which can be broadly used in many areas. Because nano-oxides are obviously superior to conventional oxide compounds in properties, the preparation and the nature of nano-oxides has been extensively investigated in the recent years.In this paper, the research situation of the nano-sized MgO and nano-sized CuAl₂O₄ are introduced. The theory, advantage and drawback of the solid-state method at lower temperature are analyzed. The nano-sized MgO and nano-sized CuAl₂O₄ were prepared by solid-state method at lower temperature using soluble starch and PEG as dispersing agents. The constituent and morphology of the as-prepared nano-oxides were characterized. And the reactive condition was improved and optimized.Nano-sized MgO were prepared by solid-state method at lower temperature using MgCl₂·6H₂O and H₂C₂O₄·2H₂O as raw materials and soluble starch and PEG1000 as dispersing agents. On different prepared conditions, the particles, crystals and rods of Nano-sized MgO were obtained, and the most smallest particle of sample is just about 3.3nm. As-burnt nano-sized MgO were characterized by IR, TG-DTA, XRD and TEM. The influence of dispersing agents was analyzed. The results indicate that when the content of the starch was 50%, and the particle size is about 3.3nm; when content of the PEG1000 was 30%, and the nano-crystals of MgO were obtained; when the content of it was 50%, and the nanorods were obtained.Nano-sized CuAl₂O₄ were prepared by a solid-state method at lower temperature, using A1(NO₃)₃ ·9H₂O,CuSO₄ ·5H₂O,K₂CO₃ and KOH as raw materials and soluble starch and PEG400 as dispersing agents. The reaction was studied by TG-DTA, XRD and TEM. The influence of dispersing agents, calcined temperature was analyzed. The results show that the crystallinity and purity of CuAl₂O₄ was good after calcined at 880℃. When the content of the starch was 50%, and the particle size is about 12nm. When the content of the PEG400 was 50%, and the nanorods of CuAl₂O₄ Nano-sized were obtained, and the length and width of nanorods is about 50nm and 8nm respectively.