Hesse Sarah A, Werner Jörg G, Wiesner Ulrich
Department of Materials Science and Engineering and ‡Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States.
Department of Materials Science and Engineering and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States.
ACS Macro Lett. 2015 May 19;4(5):477-482. doi: 10.1021/acsmacrolett.5b00095. Epub 2015 Apr 13.
Hierarchically porous materials are becoming increasingly important in catalysis, separation, and energy applications due to their advantageous diffusion and flux properties. Here we present the synthesis of hierarchically macro- and mesoporous carbon materials with graded porosity from a one-pot fabrication route. Organic-polymeric hybrids of a carbon precursor and poly(isoprene)--poly(styrene)--poly(4-vinylpyridine) with graded porosity are obtained via coassembly and nonsolvent-induced phase separation. The membranes were carbonized at temperatures as high as 1100 °C with simultaneous decomposition of the block copolymer. The carbon materials show an open nanoporous top surface with narrow pore-size distribution that opens up into a graded macroporous support with increasing macropore size along the film normal and mesoporous walls, providing for highly accessible porosity with a large surface area of over 500 m g. Further, we expand the direct synthesis process to form well-dispersed metal nanoparticles (such as nickel and platinum) on the graded, hierarchically porous carbon materials. Our one-pot synthesis offers a facile approach to graded macro- and mesoporous carbons.
由于其有利的扩散和通量特性,分级多孔材料在催化、分离和能源应用中变得越来越重要。在此,我们展示了一种通过一锅法制备路线合成具有分级孔隙率的分级大孔和介孔碳材料的方法。通过共组装和非溶剂诱导相分离,获得了具有分级孔隙率的碳前驱体与聚(异戊二烯)-聚(苯乙烯)-聚(4-乙烯基吡啶)的有机聚合物杂化物。在高达1100°C的温度下对膜进行碳化,同时使嵌段共聚物分解。碳材料显示出具有窄孔径分布的开放纳米多孔顶表面,该表面通向沿膜法线方向大孔尺寸逐渐增加的分级大孔载体和介孔壁,提供了具有超过500 m²/g大表面积的高度可及孔隙率。此外,我们扩展了直接合成工艺,以在分级的分级多孔碳材料上形成分散良好的金属纳米颗粒(如镍和铂)。我们的一锅法合成提供了一种制备分级大孔和介孔碳的简便方法。