TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The process involves heating (a) in the further presence of sacrificial metal, and heating (a) to at most200 (preferably 50 - 200)degreesC. When the fluid comprises inert organic solvent, the method involves heating (a) to at most200 (preferably at most100, especially at most80)degreesC; and refluxing the solvent (preferably benzene or pentane). The halogenated hydrocarbon is contacted with the catalyst comprising metal encapsulated dendrimeric material in an organic solvent (preferably hydrocarbon, especially benzene or pentane) in the further presence of an active metal (preferably sodium, potassium or calcium, especially potassium) (where the solvent does not react with the active metal). When (b) comprising metal encapsulated dendrimeric material is used, the method is carried out at at most200 (preferably at most150, especially at most100, particularly at most25)degreesC, or at about room temperature.Preferred Components: The sacrificial metal is metallic compound in a form such that halogen from the decomposition of the carbon source reacts with the sacrificial metal. (b) Is iron-encapsulated dendrimeric material and comprises hyperbranched molecule. The fluid comprises supercritical fluid (preferably carbon dioxide, krypton, xenon, ethane, methane or propane) (preferably supercritical carbon dioxide). The sacrificial metal is copper, titanium, vanadium, nickel, iron, zinc (preferably copper or zinc), alkali metal or alkaline earth metal (preferably sodium, potassium, magnesium or calcium, especially potassium). (a) Is a tetrahalomethane of formula CX4 (preferably carbon tetrachloride or carbon tetraiodide). When (b) comprises metal encapsulated dendrimeric material, the halogenated hydrocarbon is of formula CX4 or C2X4.X = Cl, Br or I.The dendrimeric material has diameter of at most 10 (preferably at most5, especially 3 - 5) nm and comprises a dendrimer (preferably poly(propyleneimine) PPI or polyamidoamine (PAMAM), especially Generation 4 PPI dendrimer). The metal encapsulated dendrimer comprises a metal in elemental form held on dendrimer molecule having diameter at most10 nm (preferably iron held on amine-terminated dendrimer or iron held on hydroxyl-terminated dendrimer) (where the dendrimer comprises Generation 4 PPI dendrimer). When the supercritical fluid comprises carbon dioxide, the heating of (a) is carried out at at most200 (preferably at most175)degreesC. EXAMPLE - Carbon tetrachloride (3 ml), iron poly(propyleneimine) dendrimer (0.006 g) and methanol (8 ml) were placed in a vial with excess copper wire wrapped around it. The vial was placed in a beaker. The beaker and vial were placed in carbon dioxide reactor at a pressure of 1200 psi and kept at 125degreesC for 24 hours. After reaction, the vial containing the iron dendrimer contained a black solid of carbon nanotube.