Method for connecting graphene and metal compound electrodes in carbon nanotube device through carbon-carbon covalent bonds

A method for connecting graphene and metal compound electrodes in a carbon nanotube device through carbon-carbon covalent bonds, the method comprising:

• 1) providing a substrate, and designing and preparing pre-patterned metal membrane electrodes on the substrate;
• 2) mixing carbon nanotubes with a volatile organic solvent to yield a dispersed suspension solution, disposing the carbon nanotube between the pre-patterned metal membrane electrodes in the dispersed suspension to allow two ends of the carbon nanotube to connect to the metal membrane electrodes, to form a carbon nanotube device;
• 3) annealing the carbon nanotube device under a mixture of nitrogen and argon, etching, by metal atoms, a part of carbon atoms at two ends of the carbon nanotube connected to the metal membrane electrodes to form notches;
• and
• 4) employing a hydrocarbon gas being selected from the group consisting of methane, ethylene, and acetylene as a carbon source, and catalytically decomposing, using a chemical vapor deposition process, the carbon source into carbon free radicals by the metal atoms of the metal membrane electrodes of the carbon nanotube device, and adsorbing the carbon free radicals on surfaces of the metal membrane electrodes or dissolving the carbon free radicals in the metal membrane electrodes, nucleating the carbon free radicals with a saturated concentration to form carbon-carbon bonds and a graphene in the notches of the carbon nanotube, the two ends of the carbon nanotube and the graphene being connected by covalent bonds.