一种磁性内核锐钛型TiO2光催化剂的制备与研究

A MAGNETIC CORE ANATASE PHOTOCATALYST FOR TiO2 PREPARATION AND RESEARCH

在水处理技术领域,TiO2光催化水处理技术因具有效率高、能耗低、适用范围广、反应条件温和等优点而被认为是最有前景的有机污染废水处理技术之一。直接应用TiO2悬浮体系处理污水要比基体负载固定TiO2体系有更高的处理效率,但是悬浮态的TiO2存在着回收困难的问题。对此,首先采用了共沉淀-水浴法制备了具有较好形貌的MnxZn1-xFe2O4软磁体颗粒,该软磁体颗粒能够在700℃以内保持良好的磁响应性;采用溶胶-凝胶法在颗粒上包覆SiO2中间层,得到了单分散球形的SiO2/MnxZn1-xFe2O4;采用水热法在其上包覆纳米锐钛型TiO2,最终得到了TiO2/SiO2/(MnxZn1-xFe2O4)磁性光催化剂,采用XRD、SEM、VSM等对其分析,结果表明:该催化剂呈单分散球形,粒径约在500 nm左右,具有明显的壳-核结构,磁性内核被SiO2严密包覆,锐钛型TiO2均匀负载其上,有灵敏的磁响应性。对毛用活性黄废水的降解实验证明了其较高的光催化活性。

In the field of water treatment technology, photocatalytic treatment technology of titanium dioxide is considered as one of the most promising organic pollutant wastewater treatment technologies because of its advantages of high efficiency, low energy consumption, wide application range and mild reaction conditions. Direct application of titanium dioxide suspension system to treat sewage is more efficient than fixed titanium dioxide system loaded on the substrate. However, it is difficult to recover suspended titanium dioxide. In this regard, the MnxZn1-xFe2O4 soft magnetic particles with good morphology were prepared by coprecipitation water bath method. The soft magnetic particles could maintain good magnetic responsivity at 700 degrees Celsius. The monodisperse spherical SiO2/MnxZn1-xFe2O4 was obtained by sol-gel method on the particles coated with SiO2 interlayer. The nano-anatase-type titanium dioxide was coated on it. Finally, the magnetic photocatalyst of titanium dioxide/SiO2/(MnxZn1-xFe2O4) was obtained. XRD, SEM and VSM were used to analyze the photocatalyst. The results showed that the catalyst was monodisperse spherical with a particle size of about 500 nm. It had obvious shell-core structure. The magnetic core was tightly coated by SiO2, and the anatase-type titanium dioxide was uniformly negative. It has a sensitive magnetic response. The degradation experiment of wool active yellow wastewater proved its high photocatalytic activity.