Simple procedure for growing highly-ordered nanofibers by self-catalytic growth

• US 20040126649A1
• Filed: 04/01/2003
• Published: 07/01/2004
• Est. Priority Date: 12/30/2002
• Status: Abandoned Application

• Current Assignee: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE/ MATERIAL RESEARCH
• Original Assignee: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE/ MATERIAL RESEARCH
• Inventors: Hsieh, Chien-Te, Lin, Hung-Hsiao, Huang, Yue-Hao, Chen, Jin-Ming, Shih, Han-Chang
• Application Number:
  US10/402,996
• Publication Number:
  US 20040126649A1
• Time in Patent Office: Days
• US Class Current: 429/58
• CPC Class Codes: C04B 2235/5264 characterised by the diameter of the fibers
• CPC Class Codes: C04B 35/62231 based on oxide ceramics
• CPC Class Codes: C04B 35/6225 Fibres based on zirconium oxide, e.g. zirconates such as PZT
• CPC Class Codes: C04B 35/62254 Fibres based on copper oxide
• CPC Class Codes: C23C 14/042 using masks
• CPC Class Codes: C25D 5/022 using masking means
• CPC Class Codes: C25D 5/50 by heat-treatment
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A low-cost, simple method for manufacturing highly-ordered nanofibers is provided. The feature of the procedure is using a self-catalytic mechanism. First of all, a porous membrane template is used as a filter to spread metal nanoparticles, which have a self-catalytic characteristic, onto a current collector. After removing, the membrane template, the nanoparticles grow and become highly-ordered nanofibers by heat treatment in an oxygen atmosphere. The nanofibers show superior field emission effects and are therefore ideal field emission sources.

Claims

1. A method for manufacturing highly-ordered nanofibers comprising the steps of:

depositing a plurality of metal nanoparticles through a plurality of nanometer holes of a template onto an electrode covered by the template;

removing the template to expose the metal nanoparticles on the electrode; and

oxidizing the metal nanoparticles to form a plurality of metal oxide nanofibers.

2. The method of claim 1, wherein the method of depositing the metal nanoparticles is selected from the group consisting of electrodeposition, spin-coating, metal oxide chemical vapor deposition (MOCVD), physical vapor deposition (PVD), electroless deposition. sol-gel, and chemical impregnation combined with heat treatment.

3. The method of claim 1, wherein the method of removing the template is selected from the group consisting of wet etching, plasma etching and heat treatment.

4. The method of claim 1, wherein the metal nanoparticle is a transition metal.

5. The method of claim 1, wherein the metal nanoparticle is selected from the group consisting of Fe, Co, Ni, Zr, Zn, and In/Sn.

6. The method of claim 1, wherein the electrode is selected from the group consisting of copper foils, nickel foils, and stainless steel coils.

7. The method of claim 1, wherein the template is selected from a group consisting of pine tree rings, wood, anodic alumina oxide (AAO), MCM-41 mesoporous molecular sieve, polycarbonate (PC) and polyester (PE).

8. The method of claim 1, wherein the cross-sectional diameter of the metal oxide nanofiber is controlled by the inner diameter of the hole on the template.

9. The method of claim 1, wherein the method of oxidizing the metal nanoparticle is achieved by placing the electrode attached with the metal nanoparticles into a furnace, supplying oxygen and performing heat treatment at a temperature below the melting point of the metal nanoparticle.

10. The method of claim 1 wherein the metal oxide nanofiber is used as field emission sources.

15. The method of claim 1, wherein the metal nanoparticle is selected from the group consisting of Fe, Co, Ni, Zr, Zn, and In/Sn.

18. The method of claim 1, wherein the cross-sectional diameter of the metal oxide nanofiber is controlled by the inner diameter of the hole on the template.

11. A highly-ordered nanofiber made of a metal oxide, which is formed through a method comprising the steps of:

depositing a plurality of metal nanoparticles through a plurality of nanometer holes of a template onto an electrode covered by the template;

removing the template to expose the metal nanoparticles on the electrode; and

oxidizing the metal nanoparticles to form a plurality of highly-ordered metal oxide nanofibers.

12. The method of claim 11, wherein the method of depositing the metal nanoparticles is selected from the group consisting of electrodeposition, spin-coating, metal oxide chemical vapor deposition (MOCVD), physical vapor deposition (PVD), electroless deposition, sol-gel, and chemical impregnation combined with heat treatment.

13. The method of claim 11, wherein the method of removing the template is selected from the group consisting of wet etching, plasma etching and heat treatment.

14. The method of claim 11, wherein the metal nanoparticle is a transition metal.

16. The method of claim 11, wherein the electrode is selected from the group consisting of copper foils, nickel foils, and stainless steel coils.

17. The method of claim 11, wherein the template is selected from a group consisting of pine tree rings, wood, anodic alumina oxide (AAO)-MCM-41 mesoporous molecular sieve, polycarbonate (PC) and polyester (PE).

19. The method of claim 11, wherein the method of oxidizing the metal nanoparticle is achieved by placing the electrode attached with the metal nanoparticles into a furnace, supplying oxygen and performing heat treatment at a temperature below the melting point of the metal nanoparticle.

20. The method of claim 11, wherein the metal oxide nanofiber is used as field emission sources.