均匀沉淀法制备ZnO、Fe/ZnO光催化剂

以六水合硝酸锌、九水合硝酸铁和CO(NH2)2为原料,采用均匀沉淀法并且改变实验条件制备了纯纳米ZnO和纳米Fe/ZnO光催化剂。通过X射线衍射(XRD)和扫描电子显微镜(SEM)对所有样品进行表征,并对部分样品进行了X射线能谱分析仪(EDS)测试。结果显示所有样品均为六方纤锌矿结构。此外,所有样品均由小颗粒聚集在一起而形成了形状、大小各不相同的团聚物或颗粒膜。而且随煅烧温度和Fe掺杂浓度的改变,Fe/ZnO样品的晶粒尺寸和表面形貌也随之变化。以甲基橙溶液作为污染物,在高压汞灯的照射下进行了光降解实验,实验结果表明:Fe掺杂Fe/ZnO样品的光催化性能相较纯纳米ZnO样品得到了改善。当Fe掺杂量为1.5%时Fe/ZnO样品的光催化性能最好;另外,适当煅烧温度也使Fe/ZnO样品的光催化活性得到了提升,其中最适煅烧温度为500℃。无论是Fe的掺杂浓度还是煅烧温度,适当的Fe的掺杂浓度和煅烧温度都有利于改善Fe/ZnO样品光催化剂的性能。

Synthesis of ZnO and Fe/ZnO photocatalyst with homogeneous precipitation method

Pure nanometer ZnO and nanometer Fe/ZnO photocatalysts are synthesized by homogeneous method and changing experimental conditions with Zn(NO3)2·6H2O,Fe(NO3)3·9H2O and CO(NH2)2 by as raw materials.All samples are characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM),and some samples are characterized by energy dispersive spectroscopy(EDS).The results show that all samples are wurtzite structure.Furthermore,all the samples are agglomerated by small particles and formed film or aggregates of different shapes and sizes.In addition,the grain size and surface morphology of Fe/ZnO samples also change with the change of calcination temperature and Fe doping concentration.The photodegradation of methyl orange solution by high-pressure mercury lamp indicates that the photocatalytic performance of Fe doped Fe/ZnO samples is improved compared with that of pure nanometer ZnO sample,and the catalytic performance is the best when Fe is doped by 1.5%.Additionally,the photocatalytic activity of Fe/ZnO samples is also improved by appropriately increasing the calcination temperature,which the optimum temperature for calcination is 500℃.Whether it is the doping concentration of Fe or the calcination temperature of prepared Fe/ZnO samples,a proper concentration of Fe or the calcination temperature is beneficial to improve the performance of photocatalyst of Fe/ZnO samples.