Alcohol-assisted hydrothermal carbonization to fabricate spheroidal carbons with a tunable shape and aspect ratio

Spheroidal carbonaceous materials were produced by one-step hydrothermal carbonization of carbohydrates, including glucose, sucrose, and starch, in the presence of alcohol. The morphologies of the carbon spheroids varied from centrosymmetric spheres to low-symmetry spheroids, and the shape and aspect ratio were highly dependent upon the alcohols and carbohydrates used. The results reveal that alcohol acts as a structure-directing agent which induces the self-assembly of colloidal carbon spheres into spheroids.