A method for constructing a solar rectenna array by growing carbon nanotube antennas between lines of metal, and subsequently applying a bias voltage on the carbon nanotube antennas to convert the diodes on the tips of the carbon nanotube antennas from metal oxide carbon diodes to geometric diodes. Techniques for preserving the converted diodes by adding additional oxide are also described.

The present disclosure relates to composite articles comprising non-linear elongated nanostructures and associated systems and methods. In certain embodiments, collections of carbon nanotubes or other elongated nanostructures can be used to provide mechanical reinforcement along multiple directions within a composite article.

Template-guided growth of carbon nanotubes using anodized aluminum oxide nanopore templates provides vertically aligned, untangled planarized arrays of multiwall carbon nanotubes with Ohmic back contacts. Growth by catalytic chemical vapor deposition results in multiwall carbon nanotubes with uniform diameters and crystalline quality, but varying lengths. The nanotube lengths can be trimmed to uniform heights above the template surface using ultrasonic cutting, for example. The carbon nanotube site density can be controlled by controlling the catalyst site density. Control of the carbon nanotube site density enables various applications. For example, the highest possible site density is preferred for thermal interface materials, whereas, for field emission, significantly lower site densities are preferable.

A chemical vapor deposition (CVD) system for forming carbon nanotubes from solid or liquid feedstock. The system includes a reactor including a housing that includes an inlet and an outlet. The housing defines an interior for receiving the feedstock, and the interior receives inert gas. The CVD system includes a first stop valve in flow communication with the inlet and a second stop valve in flow communication with the outlet. The first and second stop valves seal the inlet and the outlet such that a static environment is formed in the interior when reacting the feedstock. A heater heats the interior to a temperature such that the feedstock is vaporized, thereby forming vaporized feedstock. The CVD system further includes a controller coupled in communication with the first and second valves and the heater. The controller is configured to selectively actuate the first and second valves and the heater.

A method for making carbon nanotube film includes providing a growth substrate having a first surface and a second surface opposite to the first surface. A catalyst layer is placed on the first surface. The growth substrate and the catalyst layer are placed in a reaction chamber. The carbon source gas and hydrogen are supplied into the reaction chamber at a growth temperature of a plurality of carbon nanotubes. An electric field is applied to the growth substrate, wherein an electric field direction of the electric field is from the first surface to the second surface. After the plurality of carbon nanotubes fly away from the growth substrate, the electric field is stopped applying to the growth substrate, and the carbon source gas and hydrogen are continually supplied into the reaction chamber.

A method is employed to separate a carbon structure, which is disposed on a seed structure, from the seed structure. In the method, a carbon structure is deposited on the seed structure in a process chamber of a CND reactor. The substrate comprising the seed structure (2) and the carbon structure (1) is heated to a process temperature. At least one etching gas is injected into the process chamber, the etching gas having the chemical formula AO.sub.mX.sub.n, AO.sub.mX.sub.nY.sub.p or A.sub.mX.sub.n, wherein A is selected from a group of elements that includes S, C and N, wherein O is oxygen, wherein X and Y are different halogens, and wherein m, n and p are natural numbers greater than zero. Through a chemical reaction with the etching gas, the seed structure is converted into a gaseous reaction product. A carrier gas flow is used to remove the gaseous reaction product from the process chamber.

A transparent electrode with a transparent substrate and a composite layer disposed thereon, wherein the composite layer includes a graphene layer and a plurality of nanoparticles, wherein the nanoparticles are embedded in the graphene layer and extend through a thickness of the graphene layer, and wherein the plurality of nanoparticles are in direct contact with the transparent substrate and a gap is present between the graphene layer and the transparent substrate.

Disclosed is an apparatus for manufacturing a carbon nanotube fiber.

Systems and methods are provided for interweaving carbon nanotubes. One embodiment comprises a layer of carbon nanotubes. The layer includes carbon nanotubes oriented in a first direction, as well as carbon nanotubes oriented in a second direction that crosses the first direction. The carbon nanotubes oriented in the second direction are interwoven through the carbon nanotubes oriented in the first direction.

Disclosed is a photodiode, which includes a graphene-silicon quantum dot hybrid structure, having improved optical and electrical characteristics by controlling the sizes of silicon quantum dots and the doping concentration of graphene. The photodiode including the graphene-silicon quantum dot hybrid structure of the present disclosure may be easily manufactured, may be manufactured over a large area, has a wide photodetection band from the ultraviolet light region to the near infrared region, and allows selective absorption energy control.