Effects of Processing Conditions on the Physical and Electrochemical Properties of Carbon Aerogel Composites

Abstract

ABSTRACTThe carbon aerogel/carbon paper composites have physical properties similar to those of monolithic carbon aerogels but do not require supercritical extraction during fabrication. The resorcinol-formaldehyde based carbon aerogel phase is intertwined between the fibers of a commercial carbon paper. The resulting composites have variable densities (0.4–0.6 g/cc), high surface areas (300–600 m2/g), and controllable pore sizes and pore distribution. The effects of the resorcinol-formaldehyde concentrations (50–70% w/v) and the pyrolysis temperature (600–1050°C) were studied in an attempt to tailor the aerogel microstructure and properties. The composite physical properties and structure were analyzed by transmission electron microscopy and multipoint-BET analyses and related to electrochemical capacitive data in 5M KOH. These thin carbon aerogel/carbon paper composite electrodes are used in experiments with electrochemical double-layer capacitors and capacitive deionization.