Facile shape and size-controlled growth of uniform magnetite and hematite nanocrystals with tunable properties  

作　　者：CHEN LiQiao LIU WeiPing CHEN JiaLin YANG XianFeng LIU Jia FU XiongHui WU MingMei 

机构地区：[1]Key Laboratory of Bioinorganic and Synthetic Chemistry, Ministry of Education,' State Key Laboratory of Optoelectronic Materials and Technologies,' School of Chemistry and Chemical Engineering, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, China [2]State Key Lab of Advanced Technology for Comprehensive Utilization of Platinum Metals,' Kunming Institute of Precious Metals, Kunming 650106, China

出　　处：《Science China Chemistry》2011年第6期923-929,共7页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China, Guangdong Province, Guangzhou City;the Ph.D. Programs Foundation of Ministry of Education of China (U0734002, 50872158, 8251027501000010, 2010GN-C011 & 20090171110025)

摘　　要：Monodispersed magnetite Fe3O4 and hematite α-Fe2O3 nanocrystals have been grown in co-solvents of alcohol and water. Either the shape or the size of the nanocrystals could be easily controlled. Both the phases and nanostructures have been characterized by powder X-ray diffraction patterns and electron microscopy. The magnetic and catalytic properties of these products were investigated and compared with each other. The obtained results clearly demonstrate that these iron oxide nanocrystals are soft ferromagnetic at room temperature and α-Fe2O3 has a more effective catalytic property on the thermal decomposition of ammonium perchlorate than Fe3O4. Based on the experimental data, it is proposed that the magnetic and catalytic properties of these nanocrystals are dependent not only on the size and shape, but also on the surface structure of the nanocrystals. The nanoplates with significant anisotropic nanostructure demonstrate a highly enhanced performance as compared to nanoparticles.Monodispersed magnetite Fe3O4 and hematite α-Fe2O3 nanocrystals have been grown in co-solvents of alcohol and water. Either the shape or the size of the nanocrystals could be easily controlled. Both the phases and nanostructures have been characterized by powder X-ray diffraction patterns and electron microscopy. The magnetic and catalytic properties of these products were investigated and compared with each other. The obtained results clearly demonstrate that these iron oxide nanocrystals are soft ferromagnetic at room temperature and α-Fe2O3 has a more effective catalytic property on the thermal decomposition of ammonium perchlorate than Fe3O4. Based on the experimental data, it is proposed that the magnetic and catalytic properties of these nanocrystals are dependent not only on the size and shape, but also on the surface structure of the nanocrystals. The nanoplates with significant anisotropic nanostructure demonstrate a highly enhanced performance as compared to nanoparticles.

关 键 词：iron oxide NANOCRYSTALS GROWTH PROPERTIES 

分 类 号：O722.4[理学—晶体学] TB383[一般工业技术—材料科学与工程]