Abstract:

Carbon aerogels (CAs) supported Pt catalysts were prepared separately by directly loading of Pt on the surface of CAs and simultaneously loading of Pt during the synthesis of CAs respectivelyXRD, TEM, ICP and electrochemical cyclic voltammograms were used to evaluate and comparatively discuss the effects of method of loading on the properties of CAs supported Pt catalystThe results showed that simultaneous loading led to large Pt particle size, poor Pt dispersion and low Pt loading quantity, resulting in poor catalytic performance for methanol oxidationOn the contrary, high performance CAs supported catalyst with well dispersed small Pt particle size could be obtained via direct loading.

Key words: 炭气凝胶, 催化剂, 负载途径, 甲醇氧化

摘要：

选择孔隙率高、孔隙尺寸小、比表面积大、电导率高、孔径大小及分布可控的新型炭材料炭气凝胶(CAs)为载体，通过在成品CAs表面负载和在CAs制备过程中同步负载两种途径制备了CAs负载的Pt催化剂，利用XRD、TEM、ICP及电化学循环伏安测试等手段对比讨论了负载途径对CAs载Pt催化剂物化性能及甲醇氧化催化活性的影响。结果表明，同步负载虽然可以简化制备工艺，但所制得的催化剂样品中催化活性组分Pt颗粒大、团聚严重、分散性差、负载量低，而且有许多Pt颗粒被包裹在CAs内部，因而导致了催化剂的有效利用率和催化性能降低。相反，通过在成品CAs表面负载的方法可以制得Pt颗粒小、分散均匀、实际负载量接近理论设计的高性能催化剂。

关键词: 炭气凝胶, 催化剂, 负载途径, 甲醇氧化