水热合成法制备纳米α-Fe_2O_3粉体及光催化性能研究

Preparation of nano α-Fe_2O_3 powders by hydrothermal synthesis method and its photocatalytic performance

以氯化铁和三乙烯四胺为原料,采用水热合成法制备了纳米α-Fe2O3。对样品进行了XRD、FT-IR、TEM表征分析,并研究了其光催化性能。研究结果表明,随着Fe Cl3与C6H18N4摩尔比的增大,纳米颗粒先增大后减小,当n（Fe Cl3）∶n（C6H18N4）=1∶1,样品为结晶度较好的50-80 nm的近方形颗粒,且分散性较好。当n（Fe Cl3）∶n（C6H18N4）=2∶1,样品颗粒最小,光催化性能最好。随着水热反应时间延长,样品颗粒尺寸减小,当水热反应0.5 h时,样品为形貌不规则、界面不清晰、有毛绒状物质附着的60-70 nm的圆形颗粒,有团聚,结晶度较差。当水热反应1 h时,样品为粒径65 nm左右的近方形均匀块状颗粒,且分散性较好,结晶度较高。继续延长水热反应时间,样品形貌变化且颗粒减小,光催化性能逐渐增强。

α-Fe2O3 samples were prepared from ferric chloride and triethylene tetramine by hydrothermal synthesis method. The samples were characterized by XRD,FT-IR and TEM,and its photocatalytic performances were studied. The results show that the particle size of the samples are increased first and than decreased as the molar ratio of Fe Cl3 and C6H18N4increasing. When the molar ratio of Fe Cl3 and C6H18N4is 1 ∶ 1,the samples are shown square particles of 50 ~ 80 nm with good crystallinity and dispersibility. When the molar ratio of Fe Cl3 and C6H18N4is 2 ∶ 1,the particle size is the smallest,and its photocatalytic performance is the optimal. The particle size of the samples is increased as the hydrothermal reaction？ time extension. When the hydrothermal reaction？ time is 0. 5 h,the samples are？ fluffy rounded particles of 60 ~ 70 nm with anomalous morphologies,fuzziness interface and poor crystallinity. After hydrothermal reaction for 1 h,the samples are homogeneous square particles of about 65 nm with good crystallinity and dispersibility. Continue to increase the hydrothermal reaction？ time,the morphologies of the samples are changed and the sizes are decreased,while its photocatalytic performance becomes better.