高温气-固反应水解制备八面体形四氧化三钻粉末

Synthesis of Microsized Co_3O_4 Octahedral by High Temperature Gas-solid Hydrolysis

提出了一种以CoCl_2·xH_2O为原料,高温气-固反应水解制备四氧化三钴粉末的新方法,实验考察了反应温度、氯化钴结晶水含量及惰性分散介质的添加对产物的影响.采用X射线衍射、扫描电镜、激光粒度分析对样品的物相、形貌、粒度等进行了表征.结果表明:制备的粉末颗粒由{111}晶面所包围,呈八面体形貌,粒度在亚微米至微米级;反应温度越高,产物粒子的粒径越大;以COCl_2·2H_2O为原料制备的粉末粒径分布范围较窄;惰性分散介质的添加改善了粉末的单分散性.简要分析了形成八面体形貌的原因及各因素对粉末形貌与粒度的影响.

A novel method,involving high temperature gas-solid hydrolysis,was proposed for the preparation of micro-Co3O4 powder.The effects of reaction temperature,crystal water content of CoCl2, the addition of inert dispersate on the product were investigated.The composition,morphology,and particle size of the prepared particle are characterized by X-ray diffraction（XRD）,Scanning electron- microscope（SEM）and Laser particle size analysis.The results indicate that the obtained powder with octahedral crystal structure are surrounded by {111} crystal surfaces.And the size ranges from submi- cron to micron,the particle size increases with the temperature elevating,the size distribution becomes narrow when COCl2·2H2O is employed as precursor.The addition of inert dispersate is beneficial to the monodispersity of the obtained powder.The reasons for the formation of octahedral crystal morphology and the influencing factors of the particle size and morphology are also discussed.