【摘要】 用溶胶-凝胶法在一定条件下制备了纯的纳米级γ-Fe₂O₃,并研究了其热稳定性。XRD结果表明,γ-Fe₂O₃在500℃温度下烧结后仍为γ-Fe₂O₃相,随着烧结温度的升高,晶型逐渐由γ相转变为α相;当烧结温度达到900℃时,γ-Fe₂O₃基本上全部转化为α-Fe₂O₃。更多还原

【Abstract】 Nano-scale γ-Fe₂O₃ were prepared by using the Sol -Gel method in ferric nitrate and iron nitrate system. The samples were characterized by XRD,TGA-DTA and TEM. The thermal stability of the γ-Fe2O3 samples was investigated. The results show that the average diameter of particles is about 20nm and that the structure of nanocrystal γ-Fe2O3 has a good stability when kept at 500℃ for 1h. But at 600℃ for lh,the γ-Fe2O3 nanocrystalline will begin to partially transform to α-Fe2O3 structure. When held at 900℃ for 1h, the γ-Fe2O3 will almost entirely change into α-Fe2O3 phase state.更多还原