Pt/C catalysts with isopropanol as both dispersant and reducing agent were synthesized by microwave-irradiated polyol method. The microstructures of the catalysts were characterized by XRD and TEM. The effects of capping agents, pH and heating rate on Pt particle size were studied. Then Pt/C catalysts were loaded on foam nickel with polytetrafluoroethylene latex to obtain hydrophobic catalysts, and their catalytic activities for hydrogen-water liquid phase exchange reaction were investigated. The results show that compared to the non-capped Pt/C catalysts, the average size of Pt particles in sodium acetate, sodium glycollate and disodium hydrogen citrate capped Pt/C catalysts decreases from 4. 4 nm to 2. 3, 2. 5, and 2. 3 nm respectively, and the agglom-eration of Pt particles becomes obscure. The mean size of Pt particles in Pt/C catalysts decreases evidently with the increasing of the heating rate. However, the mean sizes of Pt particles in the Pt/C catalysts prepared with different pH of the synthesis solution are similar. The activity of the hydrophobic catalysts with capping agents is high for hydrogen-water liquid exchange reaction, and is enhanced by decreasing the average particle size, in the range of 2. 3-4. 4 nm.%以异丙醇为分散溶剂与还原剂,采用高压微波加热法制备了Pt/C催化剂,研究了不同实验条件对Pt尺寸的影响,利用XRD、TEM对催化剂进行了表征.再将Pt/C催化剂和聚四氟乙烯混合,负载至泡沫镍上得到疏水催化剂,研究其对氢-水液相催化交换反应的催化性能.结果表明:加入保护剂乙酸钠、羟基乙酸钠、柠檬酸氢二钠后,Pt/C催化剂的活性金属团聚现象减少,Pt平均尺寸明显减小(由4.4 nm分别降低到2.3、2.5、2.3 nm)；升温速率对Pt尺寸影响较大,随着升温速率的提高,活性金属Pt的尺寸减小；而pH的变化对Pt粒子的尺寸影响较小.加入保护剂有利于氢-水交换反应的催化剂活性,Pt尺寸为2.3～4.4 nm时,催化剂活性随Pt尺寸减小而提高.
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