摘要
采用超声-微波法结合热转化反应,以Zn5(OH)8(AC)2.2H2O为前驱体,以NaBF4和离子液体C7H13BrN2为导向剂快速合成了带状、棒状和粒状氧化锌光催化剂,并利用XRD和SEM对其结构与形貌进行了表征.测试了3种不同形貌的氧化锌对甲基橙的光催化活性并与商品TiO2(P25)的活性相比较,发现在反应进行390 min后,3种ZnO对甲基橙的降解率分别达到了66.6%、20.5%和66.4%,其中带状和粒状ZnO纳米结构的降解率都远高于TiO2(P25)的降解率28%.研究表明,带状和粒状ZnO纳米结构的高活性与其较高的比表面积有关,而其比表面积又与其形貌及微结构有关.由ZnO纳米带的表面光电压谱发现其光伏响应阈值为3.4 eV,且其表现出p-型半导体特性.
ZnO nanobehs, rods and nanoparticles were rapidly synthesized by ultrasound-microwave method combining with thermal conversion using Zn5 （OH）8（AC）2 ·2H2O as a precursor, and NaBF4 and the ionic liquid C7H13 BrN2 as oriented agents. Their crystalline structures and morphologies were characterized by XRD and SEM, respectively. Photocatalytic activi- ties of the three ZnO products with different morphologies on methyl orange were investigated and compared with that of the commercial TiO2 （ P25 ）. It was found that the photodegradation percentages of the three ZnO on methyl orange reached 66. 6%, 20.5% and 66.4%, respectively after 390 min reactions. Especially, the degradation percentages of the ZnO nanobe-Its and nanoparticles are both much higher than that of the TiO2 （P25） , 28%. It was shown that the high photocatalytic activities of the ZnO nanobelts and nanoparticles are close related with their high surface area ratios which are determined by their morphologies and micro-structures. Using surface photovoltage spectrum, the photovoltaic threshold of the ZnO nanobe- Its was determined as 3.4 eV and was found a characterization of a p-type semiconductor.
出处
《天津理工大学学报》
2010年第3期7-10,共4页
Journal of Tianjin University of Technology
基金
国家自然科学基金(20871091)
天津市科委自然科学基金(07JCYBJC18600)
关键词
氧化锌
超声-微波法
光催化
表面光伏
ZnO
utrasound-microwave method
photocatalysis
surface photovoltaic
