Structural changes in carbon produced by a sulfur-aided catalytic chemical vapor deposition

Branched carbon structures were formed by a chemical vapor deposition of toluene using ferrocene as a catalyst precursor and thiophene as a promoter. The effects of sulfur on the carbon products were investigated by SEM, XRD, and EDX. Results show that the product microstructure changes from tree-like to worm-like when the thiophene volume fraction in the toluene increases from 0.01 to 1%. The carbon trees consist of long, straight, and well-developed branches, while the worm carbons are composed of short and curled fibers. There is no obvious difference in d002, La and Lc for the two products.