纳米ZnO的制备及其在不同牺牲试剂下的光催化产氢性能

采用沉淀法与异相共沸蒸馏技术相结合制备了ZnO纳米粉体，并利用X射线粉末衍射、扫描电镜、透射电镜和液氮吸-脱附等技术对制备的样品进行了分析与表征．考察了Pt的负载量、煅烧温度以及牺牲试剂的种类和浓度对制备的纳米ZnO的光催化产氢效率的影响．结果表明：与其他温度下煅烧获得的产物相比，400 oC煅烧产物表现出最佳的光催化产氢效率，且以甲醇为牺牲试剂时纳米ZnO悬浮体系的光催化产氢效率远高于以三乙醇胺为牺牲试剂时的产氢效率．其原因在于光催化过程中甲醇氧化也对体系的产氢有贡献．此外，探讨了基于实验结果对含甲醇的

Preparation of ZnO Nanoparticles and Photocatalytic H2 Production Activity from Different Sacrificial Reagent Solutions

ZnO nanoparticles were synthesized via a direct precipitation method followed by a hetero-geneous azeotropic distillation and calcination processes, and then characterized by X-ray power diffraction, scanning electron microscopy, transmission electron microscopy, and ni-trogen adsorption-desorption measurement. The effects of Pt-loading amount, calcination temperature, and sacrificial reagents on the photocatalytic H₂ evolution efficiency from the present ZnO suspension were investigated. The experimental results indicate that ZnO nanoparticles calcined at 400 oC exhibit the best photoactivity for the H₂ production in comparison with the samples calcined at 300 and 500 oC, and the photocatalytic H₂ pro-duction efficiency from a methanol solution is much higher than that from a triethanolamine solution. It can be ascribed to the oxidization of methanol also contributes to the H2 produc-tion during the photochemical reaction process. Moreover, the photocatalytic mechanism for the H₂ production from the present ZnO suspension system containing methanol solution is also discussed in detail.