Method and apparatus for growing fullerene nanotube forests, and forming nanotube films, threads and composite structures therefrom

Abstract

The present invention provides apparatus and methods for growing fullerene nanotube forests, and forming nanotube films, threads and composite structures therefrom. In some embodiments, an interior-flow substrate includes a porous surface and one or more interior passages that provide reactant gas to an interior portion of a densely packed nanotube forest as it is growing. In some embodiments, a continuous-growth furnace is provided that includes an access port for removing nanotube forests without cooling the furnace substantially. In other embodiments, a nanotube film can be pulled from the nanotube forest without removing the forest from the furnace. A nanotube film loom is described. An apparatus for building layers of nanotube films on a continuous web is described.

1 . A nanotube article comprising:
 a plurality of nanotube films stacked in a continuous web, the plurality of nanotube films including:
 a first nanotube film having nanotubes substantially aligned in a first direction, the first direction being at a first angle relative to a length-wise edge of the web; and 
 a second nanotube film having nanotubes substantially aligned in a second direction, the second direction being at a second angle relative to the length-wise edge of the web, wherein the second angle is different than the first angle. 
   
     
     
         2 . The article of  claim 1 , wherein the web is densified and wound on a take-up roll. 
     
     
         3 . The article of  claim 1 , wherein each of the plurality of nanotube films includes carbon fullerene nanotubes. 
     
     
         4 . The article of  claim 1 , wherein the web includes a first set of parallel nanotube films that is woven into a second set of parallel nanotube films. 
     
     
         5 . The article of  claim 1 , wherein the web includes a first set of films having a plurality of nanotube warp films oriented at the first angle to the length-wise edge of the web woven with a second set of films having a plurality of nanotube weft films oriented at the second angle to the length-wise edge of the web. 
     
     
         6 . The article of  claim 1 , wherein the web includes a first set having a plurality of nanotube films parallel to one another and crossed-but-not-woven with a second set having a plurality of nanotube films parallel to one another. 
     
     
         7 . An apparatus for continuous fabrication of a carbon nanotube film comprising:
 a first film-transport mechanism having one or more nanotube-film-holding surfaces, and movable along a first fabrication path; and   a layer-build-up mechanism operable to place carbon nanotube film across the nanotube-film-holding surfaces while the one or more nanotube-film-holding surfaces are moving along the fabrication path.   
     
     
         8 . The apparatus of  claim 7 , wherein the nanotube-film-holding surfaces include one or more adhesive surfaces along a surface of a flexible sheet belt, wherein the layer-build-up mechanism lays each film at a non-parallel non-perpendicular angle to a lengthwise edge of the sheet belt, and wherein the nanotube film is placed across the belt and held by the one or more adhesive surfaces, the apparatus further comprising a second film transport mechanism having a plurality of spaced-apart adhesive surfaces on a sheet belt, and movable along a second fabrication path that connects to the first fabrication path in a manner to allow transfer of the nanotube film from the first film transport mechanism to the second film transport mechanism. 
     
     
         9 . The apparatus of  claim 7 , wherein the layer-build-up mechanism includes a first set of one or more warp-film holders operable to hold a first set of warp films stretched to a first adhesive strip along a distal first edge of the first film-transport mechanism from the first set warp-film holders, and a second set of warp film holders operable to hold a second set of warp films stretched to the first adhesive strip, wherein the first film-transport mechanism includes a second adhesive strip along a second edge opposite the first edge, and a weft-film placement mechanism operable to place a weft film in a shed between the first set of warp films and the second set of warp films and attach opposite ends of the weft to the first and second adhesive strips respectively and then separate from the attached weft. 
     
     
         10 . The apparatus of  claim 9 , wherein the first set warp-film holders moves in a direction opposite relative to the second set warp-film holders after deposition of a weft film placed from the first adhesive strip to the second adhesive strip, and wherein the warp-film holders successively attach a near end of each warp film to the second adhesive strip as it completes its weave and then separate from the attached warp. 
     
     
         11 . The apparatus of  claim 7 , wherein the first film-transport mechanism includes a vacuum table, wherein the nanotube-film-holding surfaces are operable to hold and release nanotube film using a gas-pressure difference, the vacuum surface movable relative to layer-build-up mechanism to position itself for a predetermined film deposition layout. 
     
     
         12 . The apparatus of  claim 7 , wherein the first film-transport mechanism includes a vacuum table, wherein the nanotube-film-holding surfaces are operable to hold and release nanotube film using a gas-pressure difference, the vacuum surface movable relative to layer-build-up mechanism to position itself for a predetermined film deposition layout. 
     
     
         13 . The apparatus of  claim 7 , wherein the layer-build-up mechanism includes a first set of one or more warp-film holders operable to hold a first set of warp films stretched to a first adhesive strip along a distal first edge of the first film-transport mechanism from the first set warp-film holders, and a second set of warp film holders operable to hold a second set of warp films stretched to the first adhesive strip, wherein the first film-transport mechanism includes a second adhesive strip along a second edge opposite the first edge, and a weft-film placement mechanism operable to place a weft film in a shed between the first set of warp films and the second set of warp films and attach opposite ends of the weft to the first and second adhesive strips respectively and then separate from the attached weft. 
     
     
         14 . The apparatus of  claim 7 , wherein the first film-transport mechanism includes a vacuum table, wherein the nanotube-film-holding surfaces are operable to hold and release nanotube film using a gas-pressure difference, the vacuum surface movable relative to layer-build-up mechanism to position itself for a predetermined film deposition layout. 
     
     
         15 . A method comprising:
 providing an interior-flow substrate having a first major face, a first nanoporous surface layer in fluid communication with the first major face, an interior flow system operable to deliver gasses to the nanoporous layer from a side or face of the substrate other than the first major face, and a nanotube-synthesis catalyst on the first nanoporous layer; and   delivering one or more nanotube-precursor gasses into the interior flow system and through the nanoporous layer to the first major face.   
     
     
         16 . The method of  claim 15 , further comprising:
 placing the interior-flow substrate in a reaction chamber of a furnace;   heating the reaction chamber to a temperature effective for forming carbon nanotubes, wherein the delivering of the gasses includes delivering carbon-bearing precursor gas into the interior flow system and through the nanoporous layer to the first major face to form carbon nanotubes thereon; and   removing the formed carbon nanotubes from the interior-flow substrate without removing the substrate from the reaction chamber.   
     
     
         17 . The method of  claim 15 , wherein the providing of the interior-flow substrate includes forming, in the first major face of the substrate, a first plurality of interior gas passages having a longest dimension that is parallel to the first major face and having a depth measured in a direction perpendicular to the first major face that is greater than a width measured in a direction parallel to the first major face. 
     
     
         18 . The method of  claim 15 , wherein the forming of the first plurality of interior gas passages includes forming the first plurality of interior gas passages having a length along a Y-direction, the method further comprising:
 forming a second plurality of gas passages that extend to a depth more distal from the first major face than the depth of the first plurality of gas passages, and wherein each of the second gas passages is configured to be in fluid communication with a plurality of the first plurality of gas passages, in order to form a flow-through substrate.   
     
     
         19 . The method of  claim 15 , wherein the delivering of gasses includes delivering one or more reactant gasses to a side or face of the substrate other than the first major face, the method further comprising:
 controlling a temperature of the reaction chamber to maintain an effective temperature for nanotube synthesis; a substrate-holding mechanism;   exhausting spent gasses from a vicinity of the first major face; and   removing nanotube product without interrupting a substantially continuous operation of the furnace at substantially its effective temperature for nanotube synthesis.   
     
     
         20 . The method of  claim 15 , wherein the substrate is a side-flow substrate, wherein the delivering of the carbon-bearing precursor gas is done from one or more sides of the substrate adjacent the first major face, and wherein the forming of the first plurality of interior gas passages includes forming the first plurality of interior gas passages having a length along a Y-direction, the method further comprising:
 holding the interior-flow substrate in a reaction chamber of a furnace;   heating the reaction chamber to a temperature effective for forming carbon nanotubes, wherein the delivering of the gasses includes delivering carbon-bearing precursor gas into the interior flow system from a side or face of the substrate other than the first major face and through the nanoporous layer to the first major face to form carbon nanotubes thereon;   controlling a temperature of the reaction chamber to maintain an effective temperature for nanotube synthesis; a substrate-holding mechanism;   exhausting spent gasses from a vicinity of the first major face; and   removing nanotube product without interrupting a substantially continuous operation of the furnace growing nanotubes at substantially its effective temperature for nanotube synthesis.