Direct synthesis of ordered mesoporous carbons from the carbonization of as-synthesized silicatriblock copolymer nanoaomposites

Abstract

In this research, ordered mesoporous carbon materials were synthesized through a simple direct synthetic method using as-synthesized silica/triblock copolymer nanocomposites. In a narrow concentration range of triblock copolymer P123, the template of mesostructured silicates, 2-D hexagonally ordered mesoporous silica is synthesized. After sulfuric acid treatment on assynthesized SBA-15/triblockcopolymer nanocomposites in order to polymerize P123 molecules and carbonization under N2 atmosphere, P123 is converted to carbon materials in the mesostructured silica. Finally, the ordered mesoporous carbon, denoted as DC-S15 (direct mesoporous carbon from as-synthesized SBA-15), is obtained through dissolving of silica materials. This method is very simple because it excludes some of the steps that had to be done generally in template synthesis of mesoporous carbon, that is, extraction or calcinations, and filling of carbon precursors. And all obtained carbons are originated from only triblock copolymer P123, the template of silica SBA-15, which has not been known as carbon precursor. Moreover, the pore structure of this mesoporous carbon is nano-pipe type reminiscent of CMK-5 obtained from the controlled polymerization of furfuryl alcohol inside the pores of SBA-15 or obtained through catalytic chemical vapor deposition (CCVD) using SBA-15 as template. This current synthetic procedure can be extended in order to synthesize other mesoporous carbons using various triblock copolymer-based mesostructured systems. Using P103, which has shorter PPO group than P123, instead of P123 in the synthesis of as-synthesized SBA-15, CMK-3 carbon is obtained. And the mesocellular carbon foams are prepared using as-synthesized MCF/P123 nanocomposites. Moreover, it is possible to synthesize DC-S15 carbon materials from the direct carbonization of mesostructured silica/triblock copolymer nanocomposites by performing the acid catalyzed sol-gel polymerization using sulfuric acid instead of hydrochloric acid.