A carbonaceous deposit from gaseous carbon compounds, consisting of filaments grown by the catalytic action of metal particles.
In general, such deposits are obtained at pressures of \(<100\ \text{kPa}\) in the temperature region \(600{-}1300\ \text{K}\) on metals such as iron, cobalt or nickel. Typical filaments consist of a duplex structure, a relatively @O04362@-resistant skin surrounding a more easily oxidizable core, with a metal particle located at the growing end of the filament. They generally range from \(0.01\) to \(0.5\ \unicode[Times]{x3BC}\text{m}\) in diameter and up to \(10\ \unicode[Times]{x3BC}\text{m}\) in length. In some systems, the metal particles are located in the middle of the filaments, and there are also examples where several filaments originate from a single particle. The filaments may be produced in different conformations, such as helical, twisted and straight.
PAC, 1995, 67, 473. (Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)) on page 488 [Terms] [Paper]