气体模板法FeMoO_4中空微球的合成及其对Cr(VI)的光催化还原

Synthesizing FeMoO_4 hollow microspheres with gas template method and its photocatalytic reduction of Cr(Ⅵ)

在乙二醇溶剂中以硝酸铁、钼酸铵为原料制备具有可见光催化活性的钼酸亚铁中空微球,通过X-射线粉末衍射、透射电子显微镜、扫描电子显微镜、X-射线光电子能谱、比表面及孔径分析等分析手段对其物相组成、结构形貌等进行了表征,并提出了纳米层状材料在气体模板上堆积形成微米球的生长机制。结果表明,制备的钼酸亚铁中空微球对Cr(Ⅵ)有良好的吸附及光催化还原能力,在可见光条件下其对Cr(Ⅵ)的光催化还原行为符合准一级动力学特征,在pH值为2时,反应速率常数为2.15×10^(-2)min^(-1)。X-射线光电子能谱、电感耦合等离子体质谱及循环实验表明,钼酸亚铁中空微球在光催化过程中具有良好的化学稳定性和稳定的光催化活性。

FeMoO4 hollow microspheres as eco-friendly materials with the visible-light activity were prepared from FeNO3 and（NH4）6 Mo7O（24） through a solvent-thermal method using ethylene glycol and HNO3 mixture as solvents.Crystal structures,compositions and morphologies of the materials obtained were characterized by X-ray diffraction,transimission electron microscope,scanning electron microscope,X-ray photoelectron spectroscopy,Brunauer-Emmett-Teller adsorption isotherm.A possible forming mechanism of FeMoO4 hollow microspheres was proposed that lamellar FeMoO4 was generated and assembled into hollow microspheres on gas templates.FeMoO4 hollow microspheres had good adsorbingreducing ability for Cr（Ⅵ）under visible light,with the reduction behavior of Cr（Ⅵ）following a firstorder kinetics with the rate constant 2.15×10^（-2）min^（-1） at pH of 2.The results of X-ray diffraction,inductively coupled plasma mass spectrometry and the cycling tests showed that the material was stable and consistently photoactive during use.