Abstract
Carbons synthesized from thermosetting resins are generally grouped into nongraphitizable carbons. Furan-resin-derived carbon is one of the well-known nongraphitizable carbons. We investigated the microstructures of furan-resin-derived carbon by cross-sectional transmission electron microscopy, and found that graphitization occurred at the surface. This is the first cross-sectional observation of surface graphitization in furan-resin-derived carbon. The surface graphite layer was approximately 20 or 30 nm in thickness in the specimen heat-treated at 3273 K for 1800 s. Atomic stacking in the layer was parallel to the specimen surface. The interior of the specimen was not graphitic but a cage structure.
