Abstract: The invention provides a sensor array with different nanodisk sensors that may be fabricated by direct site-specific dip-pen nanopatterning (DPN) using precursor inks. The good flow characteristics and strong affinity of the sols to measurement electrodes enable intimate ohmic contact. The measurable, reproducible and proportionate changes in the resistance of the sensors when exposed to trace quantities of oxidative and reducing gases constitute the basis for nanodisk gas sensors. The nanodisk sensors show rapid response and ultra-fast recovery for the detection of nitrogen dioxide and acetic acid vapor. Based on the principles of pattern recognition of the olfactory system, an electronic nose that can “smell” different gaseous species is provided with the multiple nanodisk sensor array.

Abstract: A direct-write method for fabricating magnetic nanostructures, including hard magnetic nanostructures of barium hexaferrite, BaFe, based on nanolithographic printing and a sol-gel process. This method utilizes a conventional atomic force microscope tip, coated with a magnetic material precursor solution, to generate patterns that can be post-treated at elevated temperature to generate magnetic features consisting of barium ferrite in its hexagonal magnetoplumbite (M-type) structure. Features ranging from several hundred nm down to below 100 nm were generated and studied using AFM, magnetic force microscopy, and X-ray photoelectron spectroscopy. The approach offers a new way for patterning functional inorganic magnetic nanostructures with deliberate control over feature size and shape, as well as interfeature distance and location.

Abstract: Method and apparatus for making composite particles, such as supported metallic catalyst particles, that involve providing a vapor of a metallic catalyst material in a carrier gas flow, providing an aerosol of support particles wherein the support particles are at a lower temperature than said vapor, and contacting the aerosol and the vapor in the carrier gas flow to form particles of the metallic catalyst material on individual support particles.

Abstract: The present invention includes a method of fabricating organic/inorganic composite nanostructures on a substrate comprising depositing a solution having a block copolymer and an inorganic precursor on the substrate using dip pen nanolithography. The nanostructures comprises arrays of lines and/or dots having widths/diameters less than 1 micron. The present invention also includes a device comprising an organic/inorganic composite nanoscale region chemically bonded to a substrate, wherein the nanoscale region, wherein the nanoscale region has a nanometer scale dimension other than height.

Abstract: In one aspect, a method of nanolithography is provided using a driving force to control the movement of a deposition compound from a scanning probe microscope tip to a substrate. Another aspect of the invention provides a tip for use in nanolithography having an internal cavity and an aperture restricting movement of a deposition compound from the tip to the substrate. The rate and extent of movement of the deposition compound through the aperture is controlled by a driving force.

Abstract: Method and apparatus for making nanoparticles of a material having a diameter of 100 nanometers or less wherein the material to be formed into nanoparticles is evaporated to form a vapor plume therein, a non-reactive entrainment gaseous atmosphere suitable for evaporation conditions is introduced to a first chamber, a gaseous jet is directed through the vapor plume in a direction to carry nanoparticles formed by quenching of the vapor plume through a flow restriction orifice between the first chamber and a second chamber downstream of the first chamber, recirculation of the gaseous jet and nanoparticles entrained therein from the second chamber to the first chamber is substantially prevented to thereby provide a second stage of the gaseous jet downstream of the orifice and substantially isolated from said first chamber for flow to the second chamber, and collecting the nanoparticles from the second stage of said gaseous jet in a collection chamber downstream from the orifice.

Abstract: Nanoparticles of a material less than about 100 nm in diameter are made by evaporating the material in an evaporation chamber residing in an entrainment chamber having a gaseous atmosphere therein. The evaporator is disposed in but isolated from the entrainment chamber, except for a gaseous jet discharge opening. A carrier gas is introduced to the evaporation chamber to carry vapor of the material in the evaporation chamber through the discharge opening into the entrainment chamber as a gaseous jet. The gaseous jet entrains the gaseous atmosphere for quenching the vapor to form nanoparticles. Solid material is supplied at a feedrate to a supply opening of the evaporation chamber, melted at an end region remote from the supply opening, and evaporated at the end region at an evaporation rate equal to the feed rate of the solid material.

Abstract: A method of synthesizing encapsulated nanocrystals inside protective shells is disclosed. This method produces nanocrystals of metals, alloys, and compounds which are individually encapsulated by protective graphite shells which completely separate the nanocrystals from the environment. A separation method is also disclosed which eliminates most of all other debris except the encapsulated nanocrystals from the preparation product.