Filamentous carbon's applications include cleaning up spills of crude oil and the creation of strong and lightweight composites.
A metal particle is typically located at the growing end of the structure, although it is sometimes found in the middle of it instead.
Other theories on the difference in properties include that the deviation is based on the formation of an intermediate phase of carbides.
[8] The nickel particles located in filamentous carbon that is grown in methane and hydrogen gas between 490 °C (914 °F) and 590 °C (1,094 °F) tend to be pear-shaped at the higher end of the temperature range.
When a copper and silica catalyst is exposed to methane and hydrogen at 927 °C (1,701 °F), hollow, long filamentous carbon structures were formed, and these also contained drops of metal.
[10] Filamentous carbon typically forms on metals, including iron, cobalt, and nickel.
[8] For instance, in the presence of methanol, at a pressure of 7 kilopascals and a temperature of 500 °C (932 °F), filamentous carbon grows on iron, but not nickel.
The allotrope has the ability to destroy catalyst support structures, thus blocking reactors.
[2] Filamentous carbon can also form when acetylene decomposes on films of palladium and silicon dioxide.
However, filamentous carbon does not form on the palladium and silicon dioxide films if they are preheated with hydrogen at temperatures of 597 °C (1,107 °F).
[4] When chlorobenzene is hydrodechlorinated over nickel and silica, highly ordered structures of filamentous carbon form.
[13] Other alkali metal bromides also allow the reaction and the formation of filamentous carbon to occur.
[18] Filamentous carbon has been known since at least 1890, when P. and L. Schützenberger observed it while passing cyanogen over red-hot porcelain.
[19] In the 1950s, it was discovered that the filaments could be produced by the reactions of gases such as hydrocarbons with metals such as iron, cobalt, and nickel.
[2] The most significant study that took place during that time was conducted by Terry Baker in the 1970s and concerned keeping filamentous carbon from growing inside the cooling pipes of nuclear reactors.