What are the other amorphous forms of carbon?
Although the crystalline forms of carbon (diamond, buckyball, and graphite) are often in the limelight, amorphous carbon materials cannot be overlooked. Along with carbon fibers, carbon black and activated carbon are also amorphous materials composed completely of carbon. Carbon black is used as a pigment, in printer’s ink, and as a filler for rubber goods. It is made by combustion of materials with a high carbon-content under oxygen-free conditions. Small parts of carbon black are like graphite, and the overall structure of carbon black is believed to consist of a folded version of the graphite network. Activated carbon, prepared from the controlled pyrolysis of organic material, is useful because of its very high surface area. It is an efficient absorbent and finds applications as filters for fish tanks, drinking water, and air pollution. Chemists use activated carbon to remove impurities from reaction mixtures. Parts of the surfaces are believed to be covered with oxidation products
