Method for the preparation of ag/c nanocomposite films by laser-induced carbonization of alkane

Patent metadata

Field	Value
Publication number	US-2016222502-A1
Application number	US-201614990174-A
Country	US
Kind code	A1
Filing date	Jan 7, 2016
Priority date	Jan 30, 2015
Publication date	Aug 4, 2016
Grant date	—

Abstract

Ag/C crystalline nanocomposite films and a method of forming the films with controllable Ag/C molar ratios using a concurrent excimer laser-induced ablation of a silver target and a hydrocarbon gas under a vacuum atmosphere. Metal/Carbon nanocomposites prepared by concurrent irradiation of a metal target, in the presence of a hydrocarbon gas, during an excimer laser induced process.

First claim

1 . A method of preparing a textured core/shell nanocomposite thin film comprising:
concurrently irradiating a metal target and a hydrocarbon gas, present within a deposition chamber, with an excimer laser beam; wherein the irradiating forms carbon in the form of graphite from the hydrocarbon gas, and nanoparticles of said metal target, and concurrently forms core/shell nanocomposite particles having a metal core covered by a graphite shell; wherein the core/shell nanocomposite particles form a nanocomposite thin film on a substrate within the deposition chamber; wherein the pressure of the hydrocarbon gas in the deposition chamber during the irradiating is within a range of 20-100 Pascals.

2 . The method claim 1 , resulting in the formation of the nanocomposite thin film within the time range of 30-90 seconds.

3 . The method of claim 1 , wherein said hydrocarbon is at least one hydrocarbon selected from the group consisting of a C 1 -C 10 alkane and a C 1 -C 10 alkene hydrocarbons.

4 . The method of claim 3 , wherein said hydrocarbon is n-hexane.

5 . The method of claim 1 , further comprising varying the pressure of the hydrocarbon gas to vary the mass ratio of carbon to metal in the core/shell nanocomposite particles.

6 . The method of claim 1 , wherein the irradiating forms core/shell nanocomposite particles having an average particle size of 5-20 nm in diameter.

7 . The method of claim 1 , wherein the nanoparticles are either spherical or cubic in form.

8 . The method of claim 1 , wherein the metal is a transitional metal selected from the group consisting of Group 9, 10, or 11 transition metals.

9 . The method of claim 8 , wherein said transition metal is silver.

10 . The method of claim 1 , wherein the excimer laser beam is generated by an excimer laser selected from the group consisting of ArF and KrF excimer lasers having a beam wavelength of 193 nm-300 nm.

11 . The method of claim 10 , wherein the excimer laser is an ArF excimer laser with a wavelength of 193 nm.

12 . The method of claim 1 , wherein the core/shell nanocomposites have absorption peaks in a range from 417 nm-525 nm and further comprise a core of silver (Ag) and a shell of carbon (C).

13 . The method of claim 1 , wherein the nanocomposite thin film is used as a coating for biomedical devices.

14 . The method of claim 13 , wherein the biomedical device is a stent.

15 : The method of claim 1 , wherein the textured nanocomposite thin film is used in solar light harvesting devices and sensors.

16 . The method of claim 1 , wherein the textured nanocomposite thin film is present on a surface of a water purification apparatus.

17 . The method of claim 16 , wherein the water purification apparatus has a plasmonic photocatalysis surface.

18 . The method of claim 16 , wherein the water purification apparatus includes a nanocomposite thin film surface-enhanced Raman spectroscopy sensor.

19 . A method for creating a silver/carbon nanocomposite from a solid silver target during an excimer laser ablation process comprising:
providing a deposition chamber; placing a silver metal target and a substrate within said deposition chamber; establishing a vacuum level within said deposition chamber so as to achieve a reduced atmospheric pressure; introducing a hydrocarbon into said deposition chamber wherein said hydrocarbon is in a vapor phase due to the reduced atmospheric pressure and furthermore wherein said hydrocarbon vapor fills said deposition chamber and is in contact with said silver target; focusing an excimer laser beam onto the silver target in contact with the gaseous hydrocarbon at a power density high enough to release cubic or spherical uniformly-sized nanoparticles of the silver from the silver substrate; concurrently irradiating said hydrocarbon gas with the excimer laser beam at a power density high enough to cause decomposition of the hydrocarbon gas; said irradiation causing a carbonization of said silver nanoparticles to form a silver/carbon nanocomposite collecting said silver/carbon nanocomposite on said substrate to form a nanocomposite thin film; wherein varying the chamber vacuum level results in fluctuation of the hydrocarbon vapor pressure in the range of 20-100 Pascals, affecting the ratio of carbon to silver in the silver/carbon nanocomposite, and furthermore resulting in deposition texture variations of the nanocomposite thin film.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Gondal Mohammed Ashraf
• FAJGAR Radek
• Yamani Zain Hassan Abdallah
• Chang Xiaofeng

Classifications

• B22F1/054

  Nanosized particles · CPC title

• B22F1/16

  Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) · CPC title

• B01J35/45

  Nanoparticles · CPC title

• C23C14/28 Primary

  by wave energy or particle radiation (C23C14/32 - C23C14/48 take precedence) · CPC title

• A61L2420/06

  Coatings containing a mixture of two or more compounds · CPC title