摘要
采用溴化1-丁基-3-甲基咪唑([Bmim]Br)离子液体辅助水热合成法制备了光催化剂Bi VO4。以高压氙灯作为可见光源,亚甲基蓝为目标污染物,考察反应温度、p H、反应时间和离子用量等制备条件对Bi VO4的可见光催化活性的影响,确定了最佳制备条件。并采用XRD、SEM和UV-Vis漫反射等分析手段对催化剂的晶相、形貌和光学特性进行了表征。结果表明,在离子液体加入量为2 m L、p H=4、反应温度为180℃、反应时间为4 h的条件下,制得的Bi VO4催化剂的可见光光催化活性最高。制得的Bi VO4为单斜相,呈分散的、大小均匀的片状,在200~500 nm范围有一个较宽的强吸收平台,具有良好的可见光催化活性,在可见光照射下对浓度为5 mg/L的亚甲基蓝的光催化脱色率达97%以上。
The photocatalysts Bi VO4 were synthesized by ionic liquid( l-butyl-3-methylimidazole bromide,[Bmim]Br)-assisted hydrothermal method. Methylene blue( MB) and high-pressure xenon lamp was used as simulated pollutant and visible-light resource,respectively,to investigate the effect of temperature,p H,reaction time and [Bmim]Br dosage on visible-light-driven photocatalytic activities. The optimal preparation condition was determined. The phase,morphology and optical properties of the samples were characterized by X-ray diffraction( XRD),scanning electron microscopy( SEM) and UV-Visible diffuse reflectance spectroscopy. The results show that the visible-light-driven photocatalytic activity of photocatalysts Bi VO4 prepared under the conditions of[Bmim]Br dosage of 2 m L,p H 4,reaction temperature of 180℃,reaction time of 4 h is the highest. The prepared Bi VO4 appears monoclinic phase and dispersed sheet with uniform size. The catalysts Bi VO4 show strong absorption platform in the range of 200 ~ 500 nm and good photocatalytic activity under visible-light irradiation. The decoloration rate of methylene blue with initial concentration of 5 mg / L,catalyzed by Bi VO4 prepared under visiblelight irradiation,can reach above 97%.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第4期1875-1880,共6页
Chinese Journal of Environmental Engineering
关键词
钒酸铋
催化剂
离子液体
可见光
催化活性
Bismuth vanadate
catalyst
ionic liquid
visible light
catalytic activity
