Faculty of Science & Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo 169-8555, Japan.
Chem Asian J. 2011 Mar 1;6(3):881-7. doi: 10.1002/asia.201000674. Epub 2010 Dec 14.
A repeating template method is presented for the synthesis of mesoporous metals with 2D hexagonal mesostructures. First, a silica replica (i.e., silica nanorods arranged periodically) is prepared by using 2D hexagonally ordered mesoporous carbon as the template. After that, the obtained silica replica is used as the second template for the preparation of mesoporous ruthenium. After the ruthenium species are introduced into the silica replica, the ruthenium species are then reduced by a vapor-infiltration method by using the reducing agent dimethylamine borane. After the ruthenium deposition, the silica is chemically removed. Analysis by transmission and scanning electron microscopies, a nitrogen-adsorption-desorption isotherm, and small-angle X-ray scattering revealed that the mesoporous ruthenium had a 2D hexagonal mesostructure, although the mesostructural ordering is decreased compared to that of the original mesoporous carbon template. This method is widely applicable to other metal systems. By changing the metal species introduced into the silica replica, several mesoporous metals (palladium and platinum) can be synthesized. Ordered mesoporous ruthenium and palladium, which are not easily attainable by the soft-templating methods, can be prepared. This study has overcome the composition variation limitations of the soft-templating method.
一种重复模板法被提出用于合成具有二维六方介孔结构的介孔金属。首先，通过使用二维六方有序介孔碳作为模板制备二氧化硅复制体（即周期性排列的二氧化硅纳米棒）。之后，将获得的二氧化硅复制体用作介孔钌的制备的第二个模板。在将钌物种引入二氧化硅复制体后，通过使用还原剂二甲胺硼烷通过蒸气渗透法还原钌物种。在钌沉积之后，通过化学方法去除二氧化硅。通过透射和扫描电子显微镜、氮气吸附-解吸等温线和小角 X 射线散射分析表明，尽管与原始介孔碳模板相比，介孔钌的有序性降低，但介孔钌具有二维六方介孔结构。该方法广泛适用于其他金属体系。通过改变引入到二氧化硅复制体中的金属物种，可以合成几种介孔金属（钯和铂）。可以制备不易通过软模板法获得的有序介孔钌和钯。本研究克服了软模板法的组成变化限制。
