Abstract: Laser pyrolysis can be used to produce directly metal vanadium oxide composite nanoparticles. To perform the pyrolysis a reactant stream is formed including a vanadium precursor and a second metal precursor. The pyrolysis is driven by energy absorbed from a light beam. Metal vanadium oxide nanoparticles can be incorporated into a cathode of a lithium based battery to obtain increased energy densities. Implantable defibrillators can be constructed with lithium based batteries having increased energy densities.

Abstract: A collection of nanoscale particles are a composite of carbon and metal oxide or silicon oxide. The composite particles have an average diameter from about 5 nm to about 1000 nm, and can be produced by laser pyrolysis. The laser pyrolysis involves the formation of a molecular stream including a metal precursor, an infrared absorber, an oxidizing agent and a carbon precursor. The pyrolysis is driven by heat absorbed from a laser beam. Furthermore, nanoparticles including titanium oxide with a rutile crystal structure have been produced.

Abstract: Polishing compositions are described that are appropriate for fine polishing to very low tolerances. The polishing compositions include particles with small diameters with very narrow distributions in size and effectively no particles with diameters several times larger than the average diameter. Furthermore, the particles generally have very high uniformity with respect to having a single crystalline phase. Preferred particles have an average diameter less than about 200 nm. Laser pyrolysis processes are described for the production of the appropriate particles including metal oxides, metal carbides, metal sulfides, SiO2 and SiC.

Abstract: A particle collection apparatus has a chamber, one or more filters and a back pressure system. The filters are located in the flow path through the system to collect the particles from an input gas stream. The back pressure system applies a pulse of gas against the flow through the system to dislodge particles collected on the filters. The dislodged particles fall to a particle drain where they are removed from the system. The particle collection apparatus can be connected to a particle synthesis apparatus. The particle collection apparatus and the particle synthesis apparatus can operated at reduced pressures.

Abstract: A method for efficiently producing particles from gas phase chemical reactions induced by a radiation beam. The apparatus includes a reaction chamber and an elongated reactant inlet, where the reaction chamber is configured to conform generally to the elongated shape of the reactant inlet. Shielding gas may be introduced to form a blanket of inert gas on both sides of the reactant stream. A feed back loop may be used to maintain the desired pressure within the reaction chamber.

Abstract: Metal vanadium oxide particles have been produced with an average diameter less than about 500 nm. The particles are produced from nanocrystalline vanadium oxide particles. Silver vanadium oxide particles, for example, can be formed by the heat treatment of a mixture of nanoscale vanadium oxide and a silver compound. Other metal vanadium oxide particles can be produced by similar processes. The metal vanadium oxide particles have very uniform properties.

Abstract: Tin oxide nanoparticles were produced with tin in a variety of oxidation states. In particular, nanoparticles of single phase, crystalline SnO2 were produced. Preferred tin oxide nanoparticles have an average diameter from about 5 nm to about 100 nm with an extremely narrow distribution of particle diameters. The tin oxide nanoparticles can be produced in significant quantities using a laser pyrolysis apparatus. Nanoparticles produced by laser pyrolysis can be subjected to further processing to change the properties of the particles without destroying the nanoscale size of the particles. The nanoscale tin oxide particles are useful for the production of transparent electrodes for use in flat panel displays.

Abstract: An aerosol delivery apparatus is used to deliver an aerosol into a reaction chamber for chemical reaction to produce reaction products such as nanoparticles. A variety of improved aerosol delivery approaches provide for the production of more uniform reaction products. In preferred embodiments, a reaction chamber is used that has a cross section perpendicular to the flow of reactant having a dimension along a major axis greater than a dimension along a minor axis. The aerosol preferably is elongated along the major axis of the reaction chamber.

Abstract: Lithium manganese oxide particles have been produced with an average diameter less than about 250 nm. The particles have a high degree of uniformity. The particles are formed by the heat treatment of nanoparticles of manganese oxide. The lithium manganese oxide particles are useful as active materials in the positive electrodes of lithium based batteries. Improved batteries result from the use of the uniform nanoscale lithium manganese oxide particles.

Abstract: Batteries based on nanoparticles are demonstrated to achieve high energy densities. Vanadium oxide nanoparticles can have several different stoichiometries and corresponding crystal lattices. The nanoparticles preferably have average diameters less than about 150 nm. Cathodes produced using the vanadium oxide nanoparticles and a binder can be used to construct lithium batteries or lithium ion batteries. The nanoparticles may have energy densities greater than about 900 Wh/kg.

Abstract: Vanadium oxide nanoparticles were produced with vanadium in a variety of oxidation states and with different crystalline lattice structures. These particles preferably have an average diameter of 150 nm or less with a narrow distribution of diameters. The particles manifest unique properties that result from the small particle size and correspondingly large surface area. A variety of the vanadium oxide nanoparticles can be produced by a versatile laser pyrolysis arrangement. These nanoparticles can be further processed to change the properties of the particles without destroying the nanoscale size of the particles.

Abstract: Electromagnetic shielding material is formed from a shielding composition made with magnetic particles and a binder, where the magnetic particles have an average diameter less than about 1000 nm and are substantially crystalline. The magnetic particles can be formed from Fe.sub.2 O.sub.3, Fe.sub.3 O.sub.4, Fe.sub.3 C, or Fe.sub.7 C.sub.3. The shielding composition can be formed into a layer or into composite particles. The binder can be a metal or an electrically conducting polymer. A conducting layer can be placed adjacent to the shielding composition. The shielding material can be used to protect sensitive electronic devices. Methods are described for forming iron oxide particles by laser pyrolysis.

Abstract: A method for the production of elemental carbon fibers and carbon particles uses highly uniform catalyst particles, preferably made by laser pyrolysis. Preferred catalyst particles include elemental iron, iron carbides or iron sulfides, generally with an average particle diameter from about 1000 nm to about 5 nm. Also, preferred catalyst particles have a narrow distribution in particle diameters as well as a cut off in particle size that the diameter distribution does not have a tail toward large diameters.

Abstract: The stoichiometry and/or crystal structure of vanadium oxide particles are altered by heating initial particles of vanadium oxide under mild conditions. The temperature is generally at least about 300.degree. C. less than the melting point of both the initial vanadium oxide particle and the product vanadium oxide particles. Preferred initial particles are vanadium oxide nanoparticles. The heating can be performed under an oxidizing atmosphere or an inert atmosphere, depending on the particular initial particles and the desired product particles.

Abstract: Polymer based solar cells incorporate nanoscale carbon particles as electron acceptors. The nanoscale carbon particles can be appropriate carbon blacks, especially modified laser black. Conducting polymers are used in the solar cells as electron donors upon absorption of light. Preferred solar cell structures involve corrugation of the donor/acceptor composite material such that increased amounts of electricity can be produced for a given overall area of the solar cell.

Abstract: An apparatus efficiently produces of particles from gas phase chemical reactions induced by a radiation beam. The apparatus includes a reaction chamber and an elongated reactant inlet, where the reaction chamber is configured to conform generally to the elongated shape of the reactant inlet. Shielding gas may be introduced to form a blanket of inert gas on both sides of the reactant stream. A feed back loop may be used to maintain the desired pressure within the reaction chamber.

Abstract: Batteries based on nanoparticles are demonstrated that achieve high energy densities. Vanadium oxide nanoparticles can have several different stoichiometries and corresponding crystal lattices. The nanoparticles preferably have average diameters less than about 500 nm and more preferably less than about 150 nm. Cathodes produced using the vanadium oxide nanoparticles and a binder can be used to construct lithium batteries or lithium ion batteries. The nanoparticles may have energy densities greater than about 900 Wh/kg.

Abstract: Electromagnetic shielding material is formed from a shielding composition made with magnetic particles and a binder, where the magnetic particles have an average diameter less than about 1000 nm and are substantially crystalline. The magnetic particles can be formed from Fe.sub.2 O.sub.3, Fe.sub.3 O.sub.4, Fe.sub.3 C, or Fe.sub.7 C.sub.3. The shielding composition can be formed into a layer or into composite particles. The binder can be a metal or an electrically conducting polymer. A conducting layer can be placed adjacent to the shielding composition. The shielding material can be used to protect sensitive electronic devices. Methods are described for forming iron oxide particles by laser pyrolysis.