Abstract
Cone-shaped graphitic whiskers (CGWs) are highly ordered turbostratic carbons with stacked hexagonal carbon layers that are conically distorted. These whiskers are produced by vapor phase carbonization with β-SiC crystal additive serving as the seed. CGWs can be generated from wood using the pyrolysis gas produced by wood, and the CGWs grow in the wood cell lumen that serves as the reaction field.
In this study, sulfuric acid intercalation of whole wood block char encapsulated with CGWs was investigated. For intercalation, the wood block char encapsulated with CGWs was used as the anode of an electrochemical oxidation “cell” under a constant electrical current in sulfuric acid. Evidence for the intercalation of both wood cell char and CGWs was obtained by Raman microspectroscopy. Exfoliation of the CGWs was observed by electron microscopy with the delamination of stacked hexagonal carbon layers owing to gasification of the sulfonate ions remaining between the hexagonal carbon layers as a result of electron irradiation. Thus, this as-is whole block treatment enabled the exfoliation of the CGWs encapsulated in the wood without the need for separation from the wood cell char.
