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以非离子型表面活性剂Brij-35为稳定剂,以水为溶剂,在常温、常压条件下利用抗坏血酸还原K2PtCl4制备了Pt纳米催化剂,采用透射电子显微镜、能量弥散X射线谱、X射线粉末衍射、热重及循环伏安扫描对催化剂进行了表征.结果表明,所制Pt纳米催化剂为尺寸均一的球形分枝结构,平均粒径为36.9nm,其中每一个Pt分枝的直径为2～4nm,长度为4～6nm.为去除表面活性剂Brij-35和副产物,开发了一种简单的多次水洗法以纯化所制Pt纳米催化剂.表征结果证明,该法可有效去除表面活性剂和副产物,所得催化剂纯度与商业Pt黑(99.9%)相当,且电化学活性比表面积更高,在氧还原反应和甲醇氧化反应中表现出更高的电催化活性.
The Pt nanocatalyst was prepared by the reduction of K2PtCl4 with ascorbic acid at room temperature and atmospheric pressure using nonionic surfactant Brij-35 as stabilizer and water as solvent. Transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray powder The results showed that Pt nanostructured catalysts were spherical and uniform in size with an average diameter of 36.9 nm, in which the diameter of each Pt branch was 2 ~ 4nm, the length of 4 ~ 6nm.In order to remove the surfactant Brij-35 and by-products, developed a simple multiple washing method to purify the Pt nanocatalyst.The characterization results show that the method can effectively remove the surfactant And the byproduct, the purity of the obtained catalyst is comparable to that of commercial Pt black (99.9%), and the electrochemically active surface area is higher, which shows higher electrocatalytic activity in the oxygen reduction reaction and the methanol oxidation reaction.