聚乙二醇辅助水热合成铁酸铋粉体及其光催化性能

PEG-assisted hydrothermal synthesis of BiFeO_3 powders and its photocatalytic property

在聚乙二醇(PEG-4000)辅助下,利用水热法以硝酸铋(Bi(NO3)3.5H2O)和硝酸铁(Fe(NO3)3.9H2O)为反应原料,KOH为矿化剂,180℃反应6h合成了不同形貌及尺寸的铁酸铋(BiFeO3)粉体,探索了PEG-4000的添加量(0、0.1、0.2、0.3mmol)对反应产物形貌及尺寸的影响.利用X射线衍射仪、红外吸收光谱仪、扫描电子显微镜、紫外可见光吸收光谱仪等对制备的BiFeO3粉体的相结构、形貌及光吸收特性进行了表征.结果表明:添加0.1mmol和0.3mmol的PEG-4000,可以得到颗粒尺寸小、形貌规整的单相钙钛矿BiFeO3粉体,即适当的添加量对产物的形貌及尺寸影响较大.UV-Vis吸收图谱表明,随着颗粒尺寸的减小,粉体的吸收带边发生了蓝移.进一步以光降解亚甲基蓝(MB)溶液,研究了制备的BiFeO3粉体的光催化性能.结果显示:所得粉体表现出良好的光催化活性,且随着粒径的减小,催化效率提高.

Single-phase bismuth ferrite （BiFeO3） powders with different morphologies and sizes have been synthesized at 180 ℃ ior b n with the carefully. And the effect of PEG-4000 addition （0, 0. 1, 0.2, 0. 3 retool） was studied on the morphology and size of BiFeO3 crystallites. The phase structure, morphology, absorption of BiFeO3 powders were characterized by using XRD, FT-IR, SEM and UV-Vis. The results show that adding suitable amount of PEG-4000 can effectively reduce the crystal size of BiFeO3 particles. When adding 0.1 mmol and 0.3 mmol PEG-4000, the single-phase perovskite structure BiFeOa particles with regular morphology and smaller size can be obtained ~ The UV-Vis absorbance spectrum reveals that the absorption edges have a blueshi^t with decrease of the size of BiFeO3 particles. Furthermore, the photocatalytic activity of BiFeO3 powders was investigated by the degradation of methylene blue （MB）. The experimental results indicate that they exhibit a pronounced photocatalytic activity for the MB decomposition. And with decrease in the particle size, the reactive actvity can he enhanced.