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Y-FeOOH 脱水可制得钴改性γ-Fe_2O_3,通过钻改性γ-Fe_2O_3的还原可制得微细金属颗粒。第一步,由 Fe(OH)_2胶体沉淀物的氧化获得γ-FeOOH 粒子,在氧化过程中加入硅酸钠(0.5～1.0at％Si)可以减少γ-FeOOH(120)晶粒的尺寸。第二步,为了保留晶体的针状并产生尽可能多的孔洞,在相对低的温度(220～290℃)下使γ-FeOOH 脱水,γ-FeOOH 晶体直接转变成γ-Fe_2O_3。第三步,借助于氢氧化钴
Y-FeOOH dehydration can be prepared cobalt modified γ-Fe_2O_3, by modifying the diamond modified γ-Fe_2O_3 can be obtained fine metal particles. In the first step, γ-FeOOH particles are obtained from the oxidation of Fe (OH) 2 colloidal precipitates. The addition of sodium silicate (0.5-1.0 at% Si) during oxidation can reduce the grain size of γ-FeOOH (120). In the second step, γ-FeOOH crystals are directly converted into γ-Fe_2O_3 at relatively low temperatures (220-290 ° C) to retain crystal acicularity and produce as many pores as possible. The third step, with the help of cobalt hydroxide