Method of making nanostructured materials
AssigneeNanophase Technologies Corporation
InventorsJohn C. Parker, Mohammed N. Ali, Byron B. Lympany
Life of this patent
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Abstract
A method and system for synthesizing nanocrystalline material. A system includes a chamber, a nonconsumable cathode shielded against chemical reaction by a working gas not including an oxidizing gas, but including an inert gas, a consumable anode vaporizable by an arc formed between the cathode and the anode, and a nozzle for injecting at least one of a quench and reaction gas in the boundaries of the arc.
Claims29
A method of synthesizing nanocrystalline material, comprising the steps of:
- providing a chamber for holding means for generating a nanocrystalline aerosol selected from the group consisting of a metal, a semiconductor and a ceramic;
- further providing a nonconsumable cathode having a longitudinal axis and shielded against chemical reaction by a working gas flow which also creates an elongated ionized arc, said working gas flow consisting essentially of a non-oxidizing gas including at least one of hydrogen gas and nitrogen gas and further including an inert gas;
- further providing in the chamber a consumable anode inclined at an angle relative to the longitudinal axis of said cathode for providing material vaporizable from said anode by said elongated ionized arc;
- providing first means for injecting a gas into the chamber;
- using said first means to inject at least one of a quench and a reaction gas within the boundaries of said elongated ionized arc and causing truncation of said arc at a point of injection, thereby establishing an arc truncation point;
- maintaining said arc between said cathode and anode by injecting the working gas and at least one of the quench and reaction gas into the chamber, and forming the nanocrystalline aerosol containing nanocrystals;
- providing second means for injecting a gas into the chamber;
- using said second means to inject a cooling gas stream into the nanocrystalline aerosol at a point downstream beyond said arc truncation point to prevent further substantial agglomeration of the nanocrystals;
- and
- cooling the nanocrystalline aerosol to form the nanocrystalline material.
The method as defined in claim I wherein said working gas flow comprises an inert gas selected from the group consisting of He, Ar, Ne, Kr and Xe.
A method of synthesizing a controlled particle size range of a nanocrystalline material, comprising the steps of:
- providing a chamber for holding means for generating a nanocrystalline aerosol selected from the group consisting of a metal, a semiconductor and a ceramic;
- further providing a nonconsumable cathode having a longitudinal axis and shielded against chemical reaction by a working gas flow which also creates an elongated ionized arc, said working gas flow consisting essentially of a non-oxidizing gas including at least one of hydrogen gas and nitrogen gas and further including an inert gas;
- further providing in the Chamber a consumable anode inclined at an angle relative to the longitudinal axis of said cathode for providing material vaporizable from said anode by said elongated ionized arc;
- providing first means for injecting into the chamber at least one of a quench gas and a reaction gas within the boundaries of said elongated ionized arc and using said first means to inject at least one of the quench gas and the reaction gas into said arc at a point, thereby causing truncation of said arc at the point of injection into the arc;
- using said first means for controlling gas flow rate to change the flow rate of at least one of said quench gas and said reaction gas to control and change the particle size range of the nanocrystalline material to be synthesized;
- maintaining said arc between said cathode and anode by injecting the working gas and the at least one of quench and reaction gas with a controlled gas flow rate into the chamber to form the nanocrystalline aerosol;
- and
- cooling the nanocrystalline aerosol to form the controlled particle size range nanocrystalline material.
Dependencies are inferred from the claim text.