Abstract:
Using processes disclosed herein, materials and structures are created and used. For example, processes can include melting boron nitride or amorphous carbon into an undercooled state followed by quenching. Exemplary new materials disclosed herein can be ferromagnetic and/or harder than diamond. Materials disclosed herein may include dopants in concentrations exceeding thermodynamic solubility limits. A novel phase of solid carbon has structure different than diamond and graphite.
Abstract:
The present invention relates to a method for the purification of α-Α1 2 O 3 whiskers previously obtained by vapor-liquid-solid deposition, under metal vapors-containing atmospheres. Said method involves the volatilization of metal impurities in controlled-atmosphere furnaces at the surface of the fibers and in the drops at the end of the fibers. The invention also relates to purified α-Α1 2 O 3 whiskers obtainable by a process as defined above and substantially free from metal impurities at the surface and at the end part of the fibers, as well as the use of the purified α-Α1 2 O 3 whiskers as defined above as fillers or reinforcement agents for the preparation of ceramic, metallic or polymeric composites.
Abstract:
A nanorod is disclosed. It includes a linear body including three or less alternating regions including a first region and a second region, wherein the first region comprises a first material comprising a first ionic material and the second region comprises a second material comprising a second ionic material.
Abstract:
The invention relates to compositions comprising nanorods and methods of making and using the same. The inclusion of nanorods can enhance the thermal conductivity of a heat-transfer medium.
Abstract:
A method of preparing nanorod arrays using ion beam implantation is described that includes defining a pattern on a substrate and then implanting ions into the substrate using ion beam implantation. Next, a thin film is deposited on the substrate. During film growth, nanotrench.es form and catalyze the formation of nanorods through capillary condensation. The resulting nanorods are aligned with the supporting matrix and are free from lattice and thermal strain effect. The density, size, and aspect ratios of the nanorods can be varied by changing the ion beam implantation and thin film growth conditions resulting in control of emission efficiency.
Abstract:
A method of preparing nanorod arrays using ion beam implantation is described that includes defining a pattern on a substrate and then implanting ions into the substrate using ion beam implantation. Next, a thin film is deposited on the substrate. During film growth, nanotrench.es form and catalyze the formation of nanorods through capillary condensation. The resulting nanorods are aligned with the supporting matrix and are free from lattice and thermal strain effect. The density, size, and aspect ratios of the nanorods can be varied by changing the ion beam implantation and thin film growth conditions resulting in control of emission efficiency.
Abstract:
Nanowhiskers are grown in a non-preferential growth direction by regulation of nucleation conditions to inhibit growth in a preferential direction. In a preferred implementation, III-V semiconductor nanowhiskers are grown on an (001) III-V semiconductor substrate surface by effectively inhibiting growth in the preferential B direction. As one example, InP nano-wires were grown by metal-organic vapor phase epitaxy directly on (001) InP substrates. Characterization by scanning electron microscopy and transmission electron microscopy revealed wires with nearly square cross sections and a perfect zincblende crystalline structure that is free of stacking faults.
Abstract:
In a method of making an elongated carbide nanostructure, a plurality of spatially-separated catalyst particles is applied to a substrate. The spatially-separated catalyst particles and at least a portion of the substrate are exposed to a metal-containing vapor at a preselected temperature and for a period sufficient to cause an inorganic nanostructure to form between the substrate and at least one of the catalyst particles. The inorganic nano-structure is exposed to a carbon-containing vapor source at a preselected temperature and for a period sufficient to carburize the inorganic nanostructure.