Patent ID: 8475761

Claim:
A method for producing carbon nanocoils, comprising following steps: (a) providing a metal substrate made from iron-containing metal or an alloy thereof; (b) forming a tin precursor on the surface of the metal substrate, wherein the tin precursor is selected from the group consisting of tin nanoparticle, SnCl 3 , (C 2 H 3 O 2 ) 2 Sn, and SnO 2 ; (c) heating the substrate and the precursor to a predetermined temperature performed under an oxygen-containing atmosphere at a temperature of 400-900° C. to form iron-tin oxides as a catalyst on the metal substrate; (d) placing the metal substrate with the catalyst thereon into a reaction furnace; and (e) introducing carbon-based gas and protective gas into the reaction furnace to grow carbon nanocoils on the surface of the catalyst.