采用微波辅助结合沉淀法制备了以Zn O为主体的纳米复合材料Ag/Zn O-Zr O2。通过X射线粉末衍射(XRD)、紫外-可见漫反射吸收光谱(UV-Vis/DRS)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和N2吸附-脱附等表征手段研究了微波辐射对Ag/Zn O-Zr O2晶型结构、形貌及表面物理化学性质的影响。结果表明,在200 W微波辐射作用下,该样品晶型结构未发生明显变化,但Ag的衍射峰明显增强,同时,其晶粒尺寸、光吸收性质和表面物理化学性质等方面则发生改变,尤其是样品Ag/Zn O-Zr O2的形貌呈现了圆形片状结构。分别在紫外和微波辅助条件下对纳米复合材料的光催化性能进行了一系列考察,同时为了进一步评价所合成样品在太阳光作用下的实用价值,又考察了Ag/Zn O-Zr O2在模拟日光条件下的光催化性能。结果显示,紫外光作用下,纳米复合材料Ag/Zn O-Zr O2的光催化活性高于市售P25以及未经微波处理的样品,且在微波辅助光催化条件下,其活性有较大程度提高。200 W微波功率下所合成样品Ag/Zn O-Zr O2在模拟日光作用下显现出较高活性。另外,根据紫外光条件下对光催化活性物种的捕获实验提出了Ag/Zn O-Zr O2可能的光催化机理。
The nanocomposite Ag/Zn O-Zr O2 was prepared by microwave-assisted during the synthetic process about Zn O with sedimentation. The effect of microwave irradiation about the crystal structure, morphology and surface physicochemical properties of Ag/Zn O-Zr O2 were well characterized by X-ray diffraction(XRD), UV-Vis diffuse reflectance spectrum(UV-Vis/DRS), Scanning electron microscope(SEM), X-ray photoelectron spectroscopy and N2adsorption-desorption determination. The results indicated that, under the function of microwave irradiation, in addition to the crystal structure was not changed, the intensity of diffraction peaks of Ag increased. At the same time, the crystalline grain sizes, light absorption properties and specific surface area were changed, especially the morphology of Ag/Zn O-Zr O2 presented circular sheet structure. The photocatalytic performance of Ag/Zn O-Zr O2 was estimated under the conditions of UV or microwave-assisted, moreover, the photocatalytic performance of Ag/Zn O-Zr O2 under the mode of simulated sunlight was investigated for its practicability under sunlight. Under the function of UV light, the results have revealed that the activities of assample were much enhanced under the condition of microwave-assisted phtocatalytic. Furthermore, Ag/Zn O-Zr O2 synthesized with microwave power 200 W showed the highest activities. The results above suggested that the photocatalytic activities of the as-sample can be enhanced by the way of microwave-assisted. In addiation, the possible photocatalytic mechanism of Ag/Zn O-Zr O2 was proposed by the trapping of the photocatalyic activity species under UV irradiation.