University of Central Florida Research Foundation Inc

University of California

Lee Chow

Dan Zhou

Guangyu Chai

Fred Stevie

Stephen Kleckley

Thomas Schenkel

Elvira Vladimirovna Anoshkina

Yauheni Rudzevich

Oleg Lupan

Yuqing Lin

Guang-Yu Chai

A capillary ionic transistor and method of using is disclosed. The method including providing a capillary pipette () having an inner surface defining a channel, and a conductive layer disposed () about electrode the channel; filling at least a portion of the channel with an ionic solution () such that an electrical double layer forms on the inner surface of the pipette; inducing an electric potential within the ionic solution sufficient to generate a longitudinal flow of ions within the channel; and inducing an electric potential in the conductive layer sufficient to alter the zeta potential of the electrical double layer and adjust the flow of ions within the ionic solution.

Capillary ionic transistor

The nanofabrication of a hydrogen gas nanosensor device from single straight and branched, tripod shaped ZnO nanorods using in-situ lift-out technique, performed in the chamber of a focused ion beam (FIB) system is disclosed. Self-assembled ZnO branched nanorods have been grown by a cost-effective and fast synthesis route using an aqueous solution deposition method and rapid thermal processing. The properties of the ZnO nanorod structures were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersion X-ray spectroscopy, transmission electron microscopy and micro-Raman spectroscopy. High quality ZnO nanorods were obtained with a 90% success rate for building nanodevices. The fabricated nanosensor can gauge 150 ppm hydrogen gas in the air at room temperature. The nanosensor has selectivity for other gases such as oxygen, methane, carbon monoxide and liquid propane gas. The ZnO nanorod sensors of the present invention also operate at low power of less than 5 microwatts.

Fabrication of ZnO nanorod-based hydrogen gas nanosensor

An easy and controllable method and system to attach a carbon nanotube to a scanning probe tip such as a scanning probe microscopy (SPM) tip using a focus ion beam (FIB) technique. The method and system includes selecting a carbon fiber by a Focus Ion Beam micromanipulator, picking up the carbon fiber with the nanotube tip, forming a slot on an SPM tip, and inserting the carbon fiber with the nanotube tip into the slot.

Method and system to attach carbon nanotube probe to scanning probe microscopy tips

Apparatus, methods, systems and devices for fabricating individual CNT collimators. Micron size fiber coated CNT samples are synthesized with chemical vapor deposition method and then the individual CNT collimators are fabricated with focused ion beam technique. Unfocused electron beams are successfully propagated through the CNT collimators. The CNT nano-collimators are used for applications including single ion implantation and in high-energy physics, and allow rapid, reliable testing of the transmission of CNT arrays for transport of molecules.

Carbon nanotube collimator fabrication and application

Carbon nanoparticles including both nanofilaments and nanotubes produced by an electrochemical deposition method from organic solutions at room temperature, in which the formation and growth of carbon nanoparticles are stimulated by the catalyst, such as iron and nickel. It has been found that the electrochemical deposition conditions have a strong influence on the growth phenomenon of the carbon nanotubes. Scanning electron microscope (SEM) and transmitting electron microscope (TEM) characterizations show that the diameter of nanotubes is of the order of approximately 100 nm, and the length of filaments can be up to approximately 50 &#x3bc;m, depending on the size of catalyst particles.

Electrochemical deposition of carbon nanoparticles from organic solutions

A method for manufacturing carbon nanotubes with an integrally attached outer graphitic layer is disclosed. The graphitic layer improves the ability to handle and manipulate the nanometer size nanotube device in various applications, such as a probe tip in scanning probe microscopes and optical microscopes, or as an electron emitting device. A thermal chemical vapor deposition reactor is the preferred reaction vessel in which a transition metal catalyst with an inert gas, hydrogen gas and a carbon-containing gas mixture are heated at various temperatures in a range between 500&#xb0; C. and 1000&#xb0; C. with gases and temperatures being adjusted periodically during the reaction times required to grow the nanotube core and subsequently grow the desired outer graphitic layer.

Carbon nanotube with a graphitic outer layer

The method for the fabrication of nano scale temperature sensors and nano scale heaters using focused ion beam (FIB) techniques. The process used to deposit metal nano strips to form a sensor is ion beam assisted chemical vapor deposition (CVD). The FIB Gaion beam can be used to decompose W(CO)molecules to deposit a tungsten nano-strip on a suitable substrate. The same substrate can also be used for Pt nano-strip deposition. The precursors for the Pt can be trimethyl platinum (CH)Pt in the present case. Because of the Gabeam used in the deposition, both Pt and W nano-strips can contain a certain percentage of Ga impurities, which we denoted as Pt(Ga) and W(Ga) respectively. Our characterization of the response of this Pt(Ga)/W(Ga) nano scale junction indicates it has a temperature coefficient of approximately 5.4 mV/&#xb0; C. This is a factor of approximately 130 larger than the conventional K-type thermocouples.

Fabrication of nano-scale temperature sensors and heaters

Carbon nanoparticles including both nanofilaments and nanotubes produced by an electrochemical deposition method from organic solutions at room temperature, in which the formation and growth of carbon nanoparticles are stimulated by the catalyst, such as iron and nickel. It has been found that the electrochemical deposition conditions have a strong influence on the growth phenomenon of the carbon nanotubes. Scanning electron microscope (SEM) and transmitting electron microscope (TEM) characterizations show that the diameter of nanotubes is of the order of approximately 100 nm, and the length of filaments can be up to approximately 50 &mgr;m, depending on the size of catalyst particles.

A method for manufacturing carbon nanotubes with an integrally attached outer graphitic layer is disclosed. The graphitic layer improves the ability to handle and manipulate the nanometer size nanotube device in various applications, such as a probe tip in scanning probe microscopes and optical microscopes, or as an electron emitting device. A thermal chemical vapor deposition reactor is the preferred reaction vessel in which a transition metal catalyst with an inert gas, hydrogen gas and a carbon-containing gas mixture are heated at various temperatures in a range between 500&deg; C. and 1000&deg; C. with gases and temperatures being adjusted periodically during the reaction times required to grow the nanotube core and subsequently grow the desired outer graphitic layer.

Carbon nanotube with a graphitic outer layer: process and application

Methods of producing fullerenes in large-macroscopic quantities inexpensively is disclosed without using solid carbon material such as graphite. In a preferred embodiment, fullerenes are formed by a hot filament CVD procedure. The fullerenes occur in the soot that forms as a by-product on the edges of the substrate holder. Mass spectrum of soot deposits shows lines corresponding to C.sub.60. From the typical concentrations of gaseous species in the diamond-growing CVD chamber, hydrocarbon species including CH.sub.3 or C.sub.2 H.sub.2 can be the precursors for the formation of fullerenes in the CVD chamber. A method of using fullerenes to enhance the properties of rubber composites is also described.

CVD method of producing and doping fullerenes

A method is provided for growing a diamond thin film on a selected substrate. First the substrate is prepared by scratching the surface thereof with diamond paste. The substrate is then confined in an enclosed space which includes high purity hydrogen and high purity methane gasses under relatively low pressure. The substrate is then irradiated with microwave energy to subject the substrate to a plasma exhibiting a first predetermined power density for a first period of time sufficient to form, on the substrate, diamond-like ball structure particles. The power density of the plasma to which the substrate is exposed is then effectively increased to a second predetermined power density and the substrate in exposed to the plasma for a second period of time sufficiently long such that (100) diamond faces grow on top of the ball structure particles. Finally, the irradiation of the substrate with the diamond-like ball structure particles thereon is continued at the second predetermined power density for a third period of time sufficient to cause the (100) faces on top of the particles to be joined together into a substantially continuous diamond film.

Growing community of inventors

Orlando, FL, United States of America

Lee Chow