纳米Co_2O_3前躯体的室温固相反应工艺研究

采用室温固相反应合成纳米Co3O4前驱体,用X-射线衍射分析(XRD)和透射电镜(TEM)等手段对前驱体的制备工艺进行了研究,就不同工艺对前驱体形貌、尺寸和产率的影响规律进行了探讨。结果表明,采用CoSO4·7H2O和H2C2O4·2H2O为原料制备的前驱体均为单斜相的CoC2O4·2H2O。在压应力作用下,前驱体的形貌主要为不规则多边形,颗粒尺寸在50～500nm范围内变化。而无压应力作用时,前驱体形貌为不规则形状,颗粒尺寸均匀,约为150～200nm。前驱体的产率与工艺参数有较大关系,对反应物分别研磨或反应物混合研磨、施加压力、升高温度和提高H2C2O4·2H2O的量将有利于提高前驱体的产率。

Research on Processing Technology of Precursor of Nano-sized Co3O4 by Solid State Reaction

The precursor of Co3O4 nano particles is synthesized through solid state reaction at ambient temperature. The effect of the processing technology on the morphology, particle size and yield is studied by X-ray diffraction (XRD) and transmission electron microscope (TEM), etc. The CoSO4·2H2O and H2C2O4·2H2O are the starting materials and all the precursors prepared through different technology are monoclinic CoC2O4·2H2O. The morphology and particle size of precursors is relative to the technology. When the precursor is prepared through high pressure, it presents an irregular polygon. The particle size arranges from 50 nm to 250 nm. When the precursor is prepared without pressure, the precursor is irregular with an particle size arranged from 100 nm to 200 nm. The result also indicates that the yield of the precursor is also relative to the technology. All the following factors are favourable for improving the yield: grinding the reagents respectively or the mixture of the reagents, improving the reaction temperature, pressing the reagents and increasing the molar ratio of H2C2O4·2H2O and CoSO4·2H2O.