Pt/C催化剂的高压微波法制备及氢同位素交换性能研究

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。

Microwave-Irradiated Polyol Method Synthesis of Pt/C Catalysts and Its Catalytic Activities for Hydrogen-Water Liquid Exchange Reaction

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 agglomeration 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.