Method for mass production of graphene and carbon tubes by deposition of carbon atoms, on flat surfaces and inside walls of tubes, generated from dissociation of a carbon-containing gas stimulated by a tunable high power pulsed laser

• US 20120048195A1
• Filed: 09/01/2010
• Published: 03/01/2012
• Est. Priority Date: 09/01/2010
• Status: Active Grant

• Current Assignee: Jaw Tian Lin
• Original Assignee: Jaw Tian Lin
• Inventors: Lin, Jaw Tian
• Granted Patent: US 8,795,434 B2
• Time in Patent Office: Days
• US Class Current: 118/712
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 2202/34 Length
• CPC Class Codes: C01B 2202/36 Diameter
• CPC Class Codes: C01B 32/16 Preparation
• CPC Class Codes: C01B 32/184 Preparation

Abstract

A method for mass production of graphene and carbon tubes is presented. A carbon-containing gas (CCG) inside a set of thin gaps formed by an array of flat plates, or small multiple bores in a cylindrical shell, is maintained under free molecular conditions at all times. A train of intermittent light pulses of a tunable high power laser beam compatible with the CCG'"'"'s major absorption bands is sent through the CCG inside the gaps, or bores, to cause dissociation of the carbon atoms from the CCG molecules in said molecules'"'"' one mean free path of flight and deposition of said atoms onto the adjacent solid surfaces (plate or bore walls) during each pulse, and after a pre-determined number of pulses to form a one-atom-thick layer of hexagonal lattice of carbon atoms. Said carbon atom layers on the flat plate surfaces are graphene, those on the shell bore walls carbon tubes. Large quantity and size, and predicted high quality of products are special features of this method.

Claims

1. A concept to create regions (within a chamber), partially confined by surfaces of a solid substrate, for a carbon-containing gas (CCG, such as methane, carbon dioxide, ethanol, ethylene, etc.) to be in free molecular conditions inside the regions, for a train of a pre-determined number of pulses of a tunable high power laser (such as helium-neon, xenon-fluoride, carbon-dioxide, hydrogen-chloride lasers, excimer lasers, etc.), compatible with the major absorption bands of the chosen CCG, to go through the regions to cause dissociation of most of the carbon atoms from the CCG molecules during one mean free path of flight of said molecules and deposition of said atoms to the adjacent surfaces of said substrate during each light pulse, and for diffusion mechanism to replenish with fresh CCG to, and empty other dissociated gas products from, the regions during each intermission between two consecutive pulses, thus avoiding inter-molecule collisions and molecule-solid surface collisions of the under-energized molecules to continuously, raise said substrate materials'"'"' temperatures, and achieving the goal of having a complete one-atom-thick layer of hexagonal lattice of carbon atoms to grow on the substrate surfaces without causing substrate materials to reach their melting point temperatures.

2. A facility, based on the concept of claim 1, for production of graphene by deposition of carbon atoms, on flat plate (substrate) surfaces, generated from dissociation of a carbon-containing gas (CCG) stimulated by a tunable high power pulsed laser compatible with the CCG'"'"'s major absorption bands, comprising a) a laser source of said laser, b) a working chamber (the chamber) equipped with two windows transparent to said laser light, a nitrogen feedline with valve to let in nitrogen gas from its source for pre-production purging, a CCG feedline with valve to let in the CCG from its source, an evacuation line with valve to exhaust, and with a pumping system, c) an array of parallel flat plates, installed inside the chamber, so positioned and oriented that the windows and the plates'"'"' gaps (the heating regions), which are filled with CCG diffused from the chamber and under free molecular conditions inside them, form a see-through view of sight so that pulses of the laser beam from its source can pass the chamber'"'"'s front window, through the heating regions to dissociate the CCG for the break-away carbon atoms to deposit onto the plate surfaces to form graphene, through the rear window and out of the chamber, d) a thermal mass outside the rear window to absorb the remaining power of the outgoing laser beam, e) a means of analysis to compute all the parameters required in running the production operation and to predict production results, and f) an operation procedure to run the production.

3. A facility, based on the concept of claim 1, for production of carbon tubes, with diameter sizes ranging from nanometers to minimeters and up, by deposition of carbon atoms, on surfaces of multiple bores inside a cylindrical shell (substrate), generated from dissociation of a carbon-containing gas (CCG) stimulated by a tunable high power pulsed laser compatible with the CCG'"'"'s major absorption bands, comprising a) a laser source of said laser, b) a working chamber (the chamber) equipped with two windows transparent to said laser light, a nitrogen feedline with valve to let in nitrogen gas from its source for pre-production purging, a CCG feedline with valve to let in the CCG from its source, an evacuation line with valve to exhaust, and with a pumping system, c) a cylindrical shell with multiple bores, installed inside the chamber, so positioned and oriented that the windows and the shell bores (the heating regions), which are filled with CCG diffused from the chamber and under free molecular conditions inside them, form a see-through view of sight so that pulses of the laser beam from its source can pass the chamber'"'"'s front window, through the heating regions to dissociate the CCG for the break-away carbon atoms to deposit onto the bores'"'"' surfaces to form carbon tubes, through the rear window and out of the chamber, d) a thermal mass outside the rear window to absorb the remaining power of the outgoing laser beam, e) a means of analysis to compute all the parameters required in running the production operation and to predict production results, and f) an operation procedure to run the production.