镂空Bi2MoO6微球的制备及其对氧氟沙星抗生素的降解性能

以钼酸钠以及五水合硝酸铋为原料,采用醇热法及高温退火制备了镂空Bi2MoO6微球光催化剂。采用X射线衍射(XRD)、红外光谱(FTIR)、场发射扫描电子显微镜(FESEM)、高分辨透射电镜(HRTEM)、物理吸附分析仪、紫外-可见漫反射(UV-Vis DRS)、荧光光谱分析(PL)以及电化学测试等分析方法分别对制备材料的晶体结构、微观形貌、比表面积和光学特性进行表征。以氧氟沙星(OFX)水溶液作为目标降解物,在可见光照射的条件下,探究了Bi2MoO6对OFX的光催化降解性能。实验结果表明:醇热法合成的球状钼酸铋的平均直径为500 nm,镂空结构使得球状Bi2MoO6的比表面积提高到片状Bi2MoO6的5倍。更大的比表面积为光催化提供了大量的吸附位点,在120 min的可见光辐射下,投放量为1 g·L^-1的Bi2MoO6对p H=7、浓度为10 mg·L^-1OFX水溶液的降解效率可达64%,而片状Bi2MoO6仅为31%。镂空球状的Bi2MoO6在强碱性环境具有优异的光催化效果,对OFX的降解率达到79%,在强碱性环境中,具有更优的光催化降解性能。

Preparation of Bi2MoO6 Microspheres with Hollow Structure and Degradation Performance of Ofloxacin Antibiotics

Hollow microsphere Bi₂MoO₆ photocatalyst was prepared by alcohol synthesis and high temperature annealing using sodium molybdate and lanthanum nitrate pentahydrate as raw materials. The microstructure, specific surface area and optical characteristics of as-prepared Bi₂MoO₆ were characterized by X-ray diffraction (XRD), infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), physical adsorption analyzer, ultraviolet-visible diffuse reflectance (UV-Vis DRS), fluorescence spectroscopy (PL) and electrochemical test. The photocatalytic performance of Bi₂MoO₆ on the aqueous solution of ofloxacin (OFX) was investigated under the visible light. The results show that average diameter (500 nm) of the hollow Bi₂MoO₆ was synthesized with as more 5 times of the specific surface area as the sheet Bi₂MoO₆. The hollow Bi₂MoO₆ provides a large number of adsorption sites for reactants. The degradation rate of OFX (pH=7, 10 mg·L^-1) by 1 g·L^-1 hollow Bi₂MoO₆ reach 64% under 120 min visible light irradiation, while the sheet Bi₂MoO₆ under the same conditions was only 31%. The hollow spherical Bi₂MoO₆ showed the excellent photocatalytic capacity in strong alkaline environment, and the degradation rate of OFXreached 79%, which has a high utilization value in alkaline environment.