论文部分内容阅读
以Zn(NO_3)_2·6H_2O和Na OH为原料,分别以无机溶剂(水)和有机溶剂(无水乙醇和乙酰丙酮的混合物)为反应介质,采用无机相碱沉淀法和有机相溶胶法,制备了两种ZnO粉体材料样品ZnO-1和ZnO-2。用X-射线衍射和扫描电镜对所制备的材料进行了结构与形貌表征,发现不同制备方法所得样品均为六方晶系纤锌矿结构,但材料的形貌有显著差异:无机相碱沉淀法制备的ZnO-1为鹅卵石状晶体,有机相溶胶法制备的ZnO-2为棒状晶体。测定了两种ZnO粉体材料对水溶液中甲基橙的吸附等温线,结果表明,ZnO-2对甲基橙的最大吸附容量达到38.9mg/g,而ZnO-1为28.8mg/g。测试了材料的光催化性能,结果表明,当甲基橙溶液初始浓度为20mg/L、ZnO样品的投加量为1g/L时,经300W高压汞灯照射3h后,ZnO-2棒状晶体对甲基橙溶液的降解率可达78.4%,所制备的材料重复使用4次均保持较高的催化活性。
Zn (NO_3) _2 · 6H_2O and NaOH were used as raw materials to synthesize Zn (NO_3) _2 · 6H_2O and NaOH as raw materials respectively. The inorganic and organic solvents (anhydrous ethanol and acetylacetone) Two ZnO powder samples ZnO-1 and ZnO-2 were prepared. The structure and morphology of the prepared material were characterized by X-ray diffraction and scanning electron microscopy. It was found that the samples obtained by different methods were all hexagonal wurtzite structure, but the morphology of the material was significantly different: The prepared ZnO-1 is a pebble-shaped crystal, and the organic-phase sol-gel ZnO-2 is a rod-shaped crystal. The adsorption isotherms of methyl orange in aqueous solution were measured for two ZnO powders. The results showed that the maximum adsorption capacity of ZnO-2 to methyl orange was 38.9 mg / g and ZnO-1 was 28.8 mg / g. The results show that when the initial concentration of methyl orange solution is 20mg / L and the dosage of ZnO sample is 1g / L, the ZnO-2 rod-shaped crystals are irradiated with 300W high pressure mercury lamp for 3h Methyl orange solution degradation rate of up to 78.4%, the preparation of the material used repeatedly for 4 times to maintain a high catalytic activity.