比表面积及金修饰对氧化锌光催化性能的影响

Effect of Surface Area and Gold Modification on Photocatalytic Activity of Zinc Oxide

采用3步反应制得大比表面氧化锌纳米晶,并用BET、XRD和TEM对氧化锌样品的比表面积、晶型以及颗粒形貌进行了表征.以X3B染料为降解对象,紫外灯为光源,研究了其光催化性能,研究发现紫外光照180 min,X3B溶液(初始浓度为1.0×10^(-4)mol/L)的降解率为99.73%,而传统方法制备的氧化锌在相同条件下,X3B的降解率仅为39.80%.结果表明:制得的大比表面氧化锌纳米晶光催化活性明显高于传统方法制得的氧化锌.考察了金修饰对氧化锌光催化活性的影响,实验结果表明:比表面积对催化剂的光催化活性影响更大.

Nanoerystalline zinc oxide with high surface area had heen prepared. The surface area, morphology and crystallite size of the catalysts were characterized by Brunauer-Emmet-Teller （BET） model, X-ray diffraction （XRD） and transmission electron microscopy （TEM）, Reactive brilliant red X3B was used as a model chemical and UV light was used as the illumination to study the photocatalytic properties of the catalysts. Nanocrystalline zinc oxide could degrade 99.73% of 1.0× 10^-4mol/L X3E solution under UV illumination for 180 min, while the ZnO powders prepared by traditional method could only degrade 39. 80 % of X3B. The results showed that nanocrystalline zinc oxide with high surface area had higher photoactivity than the ZnO powders prepared by traditional method. In addition, the photocatalytic activity of zinc oxide modified by gold particles was also studied. The results indicated that specific surface area had a greater impact than gold modification to the photocatalytic activity of the catalysts.