"Brick-and-mortar" self-assembly approach to graphitic mesoporous carbon nanocomposites

Abstract

Mesoporous carbon materials do not have sufficient ordering at the atomic scale to exhibit good electronic conductivity. To date, mesoporous carbons having uniform mesopores and high surface areas have been prepared from partially-graphitizable precursors in the presence of templates. High temperature thermal treatments above 2000 °C, which are usually required to increase conductivity, result in a partial or total collapse of the mesoporous structures and reduced surface areas induced by growth of graphitic domains, limiting their applications in electric double layer capacitors and lithium-ion batteries. In this work, we successfully implemented a "brick-and- mortar" approach to obtain ordered graphitic mesoporous carbon nanocomposites with tunable mesopore sizes below 850 °C without using graphitization catalysts or high temperature thermal treatments. Phenolic resin-based mesoporous carbons act as mortar to highly conductive carbon blacks and carbon onions (bricks). The capacitance and resistivity of final materials can be tailored by changing the mortar to brick ratios. Ordered mesoporous carbons having graphitic carbon nanoparticles are prepared in a one-pot synthesis route by "brick-and-mortar" self-assembly using onion-like carbons, or carbon black ("bricks") and phenolic resin ("mortar") in the presence of triblock copolymers. Mesopore widths, electrical series resistance, and capacitance can be tailored by brick selection and contents in final nanocomposites. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.