摘要:
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以共沉淀法制备的钛和铬的摩尔比为4∶6的TiO2/Cr2O3纳米复合粉体为前驱体,氨气为氮化剂,制备了钛铬双金属氧氮化物纳米粉体。采用Auger电子能谱、X射线衍射、透射电子显微镜、BET比表面积、电子探针等技术对氧化物复合粉体和合成氧氮化物粉体进行了表征。结果表明:前驱体组成均匀、比表面积大、反应活性高,800℃氮化8h可以合成X射线衍射纯立方相钛铬双金属氧氮化物纳米粉体。粉体呈球形,晶粒尺寸在20~35nm,比表面积达35.62m2/g,基本无团聚。氮化前后粉体的氧含量和氮含量发生了明显变化,粉体的组成可以用Ti0.4Cr0.6OxNy表示。
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Nanocrystalline bimetallic oxynitride, Ti_(0.4)Cr_(0.6)O_(x)N_(y), was synthesized by ammonolysis of the nanosized Cr_(2)O_(3)/TiO_(2) composite powder with n(Ti)∶n(Cr)=4∶6 at 800 ℃ for 8 h. Auger electron spectroscope (AES), X-ray diffraction analysis (XRD), electron probe microanalysis (EPMA), transmission electron microscopy (TEM), and BET (BrunauerEmmettTeller) surface area techniques were used to characterize the precursor and the as-synthesized oxynitride powders. The results indicate that the precursor is a homogenous mixture of Cr_(2)O_(3) and TiO_(2) and its BET surface area is as high as 93.54 m~(2)/g. The pure bimetallic oxynitride powder with cubic structure can be obtained by nitridation at 800 ℃ for 8 h. The as-synthesized bimetallic oxynitride powder is spherical in shape and of low agglomeration. The BET surface area of the oxynitride powder is (35.62) m~(2)/g and the particle size is in the range of 20—35 nm. It is found that there are obvious changes in the contents of oxygen and nitrogen in the powder before and after nitridation, and the composition of the powder can be expressed as Ti_(0.4)Cr_(0.6)O_(x)N_(y).
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基金项目:
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国家重点基础研究发展规划(G1999064506)资助项目
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作者简介:
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参考文献:
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