Abstract:
Multicomponent nanoparticles include two or more dissimilar components selected from different members of the group of noble metals, base transition metals, alkali earth metals, and rare earth metals and/or different groups of the periodic table of elements. The two or more dissimilar components are dispersed using a polyfunctional dispersing agent such that the multicomponent nanoparticles have a substantially uniform distribution of the two or more dissimilar components. The polyfunctional dispersing agent may include organic molecules, polymers, oligomers, or salts of these. The molecules of the dispersing agent bind to the dissimilar components to overcome same-component attraction, thereby allowing the dissimilar components to form multicomponent nanoparticles. Dissimilar components such as iron and platinum can be alloyed together using the dispersing agent to form substantially uniform multicomponent nanoparticles, which can be used alone or with a support. At least a portion of the dispersing agent is removed by reduction and/or oxidation.
Abstract:
A method for manufacturing stable concentrated colloids containing metal nanoparticles in which the colloid is stabilized by adding a base. This allows the metal particles to be formed in higher concentration without forming larger agglomerates and/or precipitating. The method of manufacturing the stable colloidal metal nanoparticles of the present invention generally includes (i) providing a solution comprising a plurality of metal atoms, (ii) providing a solution comprising a plurality of organic agent molecules, each organic agent molecule comprising at least one functional group capable of bonding to the metal atoms, (iii) reacting the metal atoms in solution with the organic agent molecules in solution to form a mixture comprising a plurality of complexed metal atoms, (iv) reducing the complexed metal atoms in the mixture using a reducing agent to form a plurality of nanoparticles, and (v) adding an amount of a base to the mixture, thereby improving the stability of the nanoparticles in the mixture. The base may be added before or after forming the nanoparticles.
Abstract:
Organically complexed nanocatalyst compositions are applied to or mixed with a carbon-containing fuel (e.g., tobacco, coal, briquetted charcoal, biomass, or a liquid hydrocarbon like fuel oils or gasoline) in order to enhance combustion properties of the fuel. Nanocatalyst compositions can be applied to or mixed with a solid fuel substrate in order to reduce the amount of CO, hydrocarbons and soot produced by the fuel during combustion. In addition, coal can be treated with inventive nanocatalyst compositions to reduce the amount of NOx produced during combustion (e.g., by removing coal nitrogen in a low oxygen pre-combustion zone of a low NOx burner). The nanocatalyst compositions include nanocatalyst particles made using a dispersing agent. They can be formed as a stable suspension to facilitate storage, transportation and application of the catalyst nanoparticles to a fuel substrate.
Abstract:
Multicomponent nanoparticles include two or more dissimilar components selected from different members of the group of noble metals, base transition metals, alkali earth metals, and rare earth metals and/or different groups of the periodic table of elements. The two or more dissimilar components are dispersed using a polyfunctional dispersing agent such that the multicomponent nanoparticles have a substantially uniform distribution of the two or more dissimilar components. The polyfunctional dispersing agent may include organic molecules, polymers, oligomers, or salts of these. The molecules of the dispersing agent bind to the dissimilar components to overcome same-component attraction, thereby allowing the dissimilar components to form multicomponent nanoparticles. Dissimilar components such as iron and platinum can be alloyed together using the dispersing agent to form substantially uniform multicomponent nanoparticles, which can be used alone or with a support. At least a portion of the dispersing agent is removed by reduction and/or oxidation.
Abstract:
Tobacco products and articles are disclosed that include a nanoparticle catalyst. The nanoparticles are capable of degrading undesirable small molecules in tobacco smoke. The nanoparticle catalyst includes a dispersing agent that inhibits the deactivation of the nanoparticle catalyst. One embodiment disclosed has a dispersing agent that anchors the nanoparticles to a support material thereby preventing agglomeration of the nanoparticles. The dispersed nanoparticles exhibit higher activity and reduce the required loading in the tobacco material.
Abstract:
Disclosed are nanoparticles formed from a plurality of two or more different components. The two or more components are dispersed using a dispersing agent such that the nanoparticles have a substantially uniform distribution of the two or more components. The dispersing agents can be poly functional small organic molecules, polymers, or oligomers, or salts of these. The molecules of the dispersing agent bind to the particle atoms to overcome like-component attractions, thereby allowing different and/or dissimilar components to form heterogeneous nanoparticles. In one embodiment, dissimilar components such as iron and platinum are complexed using the dispersing agent to form substantially uniform heterogeneous nanoparticles. Methods are also disclosed for making the multicomponent nanoparticles. The methods include forming suspensions of two or more components complexed with the dispersing agent molecules. The suspensions can also be deposited on a support material and/or anchored to the support.
Abstract:
Supported catalysts include a solid support such as silica that is functionalized to have inorganic acid functional groups attached thereto. Active catalyst particles are supported on the functionalized support material. The acid functionalized support material is made by reacting a solid support with an inorganic acid containing agent such as sulfuric acid or para-toluene sulfonic acid. An organic anchoring agent is used to form and anchor catalyst nanoparticles to the acid functionalized support material. The supported catalyst can be sized and shaped for use in any type of reactor, including a fixed bed or fluidized bed reactor. The methods of the present invention also include a process for the direct synthesis of hydrogen peroxide using the supported catalyst.
Abstract:
Intermediate precursor compositions for use in manufacturing supported reactive catalysts having a controlled coordination structure, and methods for manufacturing such precursor compositions are disclosed. The precursor compositions include a catalyst complex formed from catalyst atoms and a control agent that is applied to a substrate. Reduction of the catalyst complex yields supported reactive catalyst in which a preponderance of the top or outer layer of atoms of the catalyst particles exhibit a controlled coordination number of 2. The supported catalysts are useful for a variety of chemical reactions, including the preparation of hydrogen peroxide with high selectivity.
Abstract:
A process is disclosed for the direct catalytic production of aqueous solutions of hydrogen peroxide from hydrogen and oxygen in the presence of a small amount of one or more water soluble organic additives (about 0.1-10% by weight). Suitable catalysts include nanometer-sized noble metal catalytic crystal particles. The catalyst particles preferably have a controlled surface coordination number of 2 to increase the selectivity of hydrogen peroxide production. The water soluble additive(s) increases catalytic activity causing significant increases in the apparent first order reaction rate constant for the direct production of aqueous hydrogen peroxide.
Abstract:
Organically complexed nanocatalyst compositions are applied to or mixed with a carbon-containing fuel (e.g., tobacco, coal, briquetted charcoal, biomass, or a liquid hydrocarbon like fuel oils or gasoline) in order to enhance combustion properties of the fuel. Nanocatalyst compositions can be applied to or mixed with a solid fuel substrate in order to reduce the amount of CO, hydrocarbons and soot produced by the fuel during combustion. In addition, coal can be treated with inventive nanocatalyst compositions to reduce the amount of NOx produced during combustion (e.g., by removing coal nitrogen in a low oxygen pre-combustion zone of a low NOx burner). The nanocatalyst compositions include nanocatalyst particles made using a dispersing agent. They can be formed as a stable suspension to facilitate storage, transportation and application of the catalyst nanoparticles to a fuel substrate.