Surface mechanical attrition treatment (SMAT) methods and systems for modifying nanostructures

Patent metadata

Field	Value
Publication number	US-9809893-B2
Application number	US-201514632864-A
Country	US
Kind code	B2
Filing date	Feb 26, 2015
Priority date	Feb 26, 2015
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

Described herein are systems and methods for performing a surface mechanical attrition treatment (SMAT) to the surface of a variety of materials including thin films, nanomaterials, and other delicate and brittle materials. In an aspect, a surface of a material is modified to a modified surface and from an original state to a modified state, wherein the modified state comprises a physical modification, a chemical modification, or a biological modification. In another aspect, a surface mechanical attrition treatment (SMAT) is applied to the modified surface of the material for a defined duration of time, wherein a condition associated with the SMAT is adjusted based on a structural composition of the material. In yet another aspect, a defined strain is imposed on the structural composition of the material based on the SMAT.

First claim

What is claimed is:

1. A method, comprising:
anodizing a surface of an initial material to generate porous nanostructures extending into the surface, resulting in an anodized surface;
applying a surface mechanical attrition treatment (SMAT) to the anodized surface to generate an anodized material comprising the anodized surface and an enhanced charge trapping property as compared to the initial material, wherein the SMAT comprises:
arranging a ball between the anodized surface of the anodized material and an ultrasonic horn connected to an ultrasonic transducer configured to convert an electrical signal into an oscillating wave, wherein the ultrasonic horn is configured to emit a first wave at a specified frequency upon an oscillation of the ultrasonic horn;
emitting, by the ultrasonic horn, the first wave at the specified frequency;
inducing movement, by the first wave, of the ball, wherein the movement of the ball is induced to occur at a target ball speed selected to achieve a reorganization of atoms of the anodized material in a lattice structure, and wherein the target ball speed is selected to be a speed at which more than the reorganization of the atoms does not substantially occur; and
colliding the ball, at the target ball speed with the anodized surface of the anodized material to achieve the reorganization of the atoms of the anodized material to comprise a lattice strain, of the anodized surface resulting in the enhanced charge trapping property of the anodized material.

2. The method of claim 1 , further comprising adjusting a level of impact between the ball and the anodized material, wherein the level of impact is adjusted from one or more adjustments to a power source that transmits energy through the ultrasonic horn for emission as the first wave.

3. The method of claim 1 , wherein the ultrasonic horn is connected to an ultrasonic converter configured to adjust an amplitude of the first wave emitted by the ultrasonic horn.

4. The method of claim 1 , wherein the ball and at least another ball deflects from the anodized material in a scattered formation subsequent to the colliding of the ball with the anodized material.

5. The method of claim 4 , further comprising modifying a size and shape of the ultrasonic horn prior to the applying the SMAT to the anodized surface of the anodized material.

6. The method of claim 1 , further comprising adjusting the target ball speed of the ball after the movement of the ball has been induced and prior to a stopping of the movement of the ball.

7. The method of claim 1 , wherein the ultrasonic horn is a bell-shaped horn, a bar-shaped horn, a composite ultrasonic horn, an exponential horn, an inserting horn, a round ultrasonic horn, or a tuned bolt-style horn.

8. The method of claim 1 , wherein the ultrasonic horn is formed of at least one of titanium, aluminum, or steel.

9. The method of claim 1 , wherein the ultrasonic horn is coated with at least one of a chrome plating, an anodized coat, or a carbide spray coat.

10. The method of claim 1 , wherein the porous nanostructures represent structural strain along lattice plains within the surface of the initial material.

11. A method, comprising:
modifying a surface of a material from an initial state to an anodized state, resulting in a modified surface;
applying a surface mechanical attrition treatment (SMAT) to the modified surface of the material for a defined duration of time, wherein the applying the SMAT comprises emitting a wave at a target frequency to induce movement of a ball at a target ball speed for a collision into the material that achieves a target structural reconfiguration comprising a rearrangement of atoms of the modified surface of the material in a lattice structure, and wherein the rearrangement of the atoms result in an enhanced charge trapping characteristic as compared to an initial structural configuration of the material;
emitting, by an ultrasonic horn, a first wave at a defined frequency, wherein the first wave contacts a ball;
colliding the ball, at the target ball speed based on the first wave contacting the ball, with the modified surface of the material, wherein a collision of the ball with the modified surface of the material achieves the rearrangement of the atoms of the modified surface of the material, and wherein the target ball speed is such that more than the rearrangement of the atoms does not substantially occur; and
generating a defined lattice strain due to the rearrangement of the atoms within the modified surface of the material based on colliding the ball with the modified surface at the target ball speed.

12. The method of claim 11 , wherein the target structural configuration comprises at least one of a first configuration comprising a structural defect or a second configuration comprising an introduction of a dopant.

13. The method of claim 11 , wherein the material is at least one of a catalyst material, a filtration material, a photovoltaic material, a supercapacitor material incorporated into a supercapacitor, an antibacterial material comprising antibacterial properties, or a water splitting material employed in a water splitting device.

14. The method of claim 11 , further comprising adjusting the defined duration of time resulting in a corresponding adjusting of a level of doping of the surface of the material.

15. A method, comprising:
affixing an initial material comprising a surface layer and a substrate layer in a chamber, wherein within the chamber are a set of balls and an ultrasonic vibration generator capable of emitting an ultrasonic vibrational force wherein the initial material is affixed in the chamber opposed to the set of balls and the ultrasonic vibration generator;
applying the ultrasonic vibrational force to the set of balls using the ultrasonic vibration generator;
colliding the set of balls with the surface layer of the initial material, wherein, as a result of an induced movement of the set of balls by the ultrasonic vibrational force, an impact between the set of balls travelling at a target ball speed and the surface layer achieves a target impact level, wherein the target ball speed is sufficiently low that more than a reorganization of atoms does not substantially occur; and
creating a lattice strain defect comprising a rearrangement of atoms in a lattice structure substantially throughout the surface layer resulting in an enhanced material comprising an enhanced charge trapping property as compared to the initial material absent the lattice strain defect.

16. The method of claim 15 , wherein the substrate layer comprises Ti, TiO 2 , or a combination of Ti and TiO 2 .

17. The method of claim 15 , wherein the lattice strain comprises a set of lattice plane formations, and wherein the respective ones of the set of lattice plane formations range in size from a sub-micron level to a micron level.

18. The method of claim 15 , further comprising coating the set of balls with a material resulting in a set of coated balls, wherein the colliding comprises colliding the set of coated balls with the surface layer of the initial material functionalizes the initial material with the enhanced charge trapping property.

Assignees

• Univ City Hong Kong

Inventors

• Lee Christohper Michael
• Li Yang Yang
• Lu Jian

Classifications

• C25D11/005 Primary

  Apparatus specially adapted for electrolytic conversion coating (apparatus in general for electrolytic coating C25D17/00) · CPC title

• C23C16/56

  After-treatment · CPC title

• C23C18/1666

  Ultrasonics · CPC title

• C23C16/4415

  Acoustic wave CVD · CPC title

• C25D11/26

  of refractory metals or alloys based thereon · CPC title