氧化锌纳米棒的水热合成及其光催化性能

以分析纯ZnO作为锌源、NaOH为矿化剂、盐酸为反应溶液pH调节剂,利用水热反应制备了花状ZnO纳米棒;采用扫描电子显微镜和X射线衍射仪分析了产物的形貌和结构,考察了水热温度以及Zn2+和OH-浓度比对产物形貌的影响;以甲基橙为目标降解物,采用紫外-可见分光光度计研究了ZnO纳米棒的光催化性能.结果表明,在水热反应温度80℃、Zn2+/OH-浓度比1∶7.5条件下所得ZnO纳米棒呈花状聚合,直径约为200nm,长度约为2μm,具有六方纤锌矿结构.当甲基橙初始浓度为30 mg.L-1、ZnO纳米棒的投放量为1.5g.L-1时,以300W紫外灯照射150min,甲基橙的降解率可达90%.

Hydrothermal synthesis and photocatalytic activity of zinc oxide nanorods

Flower-like ZnO nanorods were synthesized by hydrothermal method with analytical reagent ZnO as the zinc source,sodium hydroxide as the mineralizing agent,and hydrochloric acid as pH-adjusting agent.The morphology and structure of as-prepared ZnO samples were analyzed by means of scanning electron microscopy and X-ray diffraction.The effects of hydrothermal reaction temperature and ratio of Zn2+ concentration to OH-concentration on the morphology of the products were investigated.Moreover,the photocatalytic activity of ZnO nanorods was evaluated with an ultraviolet-visible light spectrophotometer while methyl orange solution was used as the target substance of degradation.It has been found that ZnO nanorods obtained at a hydrothermal reaction temperature of 80 ℃ and Zn2+/OH-concentration ratio of 1∶7.5 appear as flower-like aggregates with a diameter of about 200 nm and a length of about 2 μm,and they have hexagonal wurtzite structure.Moreover,when the concentration of methyl orange is 30 mg · L-1 and the dosage of ZnO nanorods is 1.5 g · L-1,the methyl orange can be degraded at a rate of over 90% under 150 min of irradiation by 300 W of ultraviolet lamp.