Method for making an actuator based on carbon nanotubes

• US 10,259,703 B2
• Filed: 09/25/2017
• Issued: 04/16/2019
• Est. Priority Date: 10/12/2016
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Original Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Inventors: Ma, He, Wei, Yang, Liu, Kai, Jiang, Kai-Li, Fan, Shou-Shan
• Primary Examiner(s): Eslami, Tabassom Tadayyon
• Application Number:
  US15/713,945
• Publication Number:
  US 20180099866A1
• Time in Patent Office: 568 Days
• Field of Search: 4272494
• CPC Class Codes: B01J 21/185 Carbon nanotubes carbon nanotubes per se C01B32/15
• CPC Class Codes: B01J 23/8472 Vanadium
• CPC Class Codes: B01J 23/888 Tungsten
• CPC Class Codes: B81B 2201/031 Thermal actuators
• CPC Class Codes: B81B 3/0024 Transducers for transforming thermal into mechanical energy or vice versa, e.g. thermal or bimorph actuators electric motors using thermal effects H02N10/00
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: F03G 7/005 Electro-chemical actuators; Actuators having a material for absorbing or desorbing gas, e.g. a metal hydride; Actuators using the difference in osmotic pressure between fluids; Actuators with elements stretchable when contacted with liquid rich in ions, with UV light, with a salt solution
• CPC Class Codes: F03G 7/012 Electro-chemical actuators
• CPC Class Codes: F03G 7/08 recovering energy derived from swinging, rolling, pitching or like movements, e.g. from the vibrations of a machine
• CPC Class Codes: F05B 2250/84 Nanomachines Nanotechnology for interacting, sensing or actuating B82Y15/00
• CPC Class Codes: H01M 4/48 of inorganic oxides or hydroxides
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The disclosure relates to a method for making an actuator based on carbon nanotubes. The method includes: providing a carbon nanotube layer; depositing a vanadium oxide (VO_x) layer on the carbon nanotube layer; and annealing the VO_x layer in an oxygen atmosphere to form a vanadium dioxide layer (VO₂) layer. Because the drastic reversible phase transition of VO₂, the actuator has giant deformation amplitude and fast response.

Claims

1. A method for making an actuator, the method comprising:

providing a carbon nanotube (CNT) layer;

applying a vanadium oxide (VO_x) layer on the carbon nanotube layer to form a VO_x/CNT composite; and

annealing the VO_x/CNT composite in an oxygen atmosphere to obtain a vanadium dioxide (VO₂) layer on the carbon nanotube layer.

2. The method of claim 1, wherein the applying the vanadium oxide layer on the carbon nanotube layer comprises:

depositing the vanadium oxide layer on a carbon nanotube film to obtain a preform composite layer, wherein a thickness of the carbon nanotube film is less than 30 nanometers; and

placing the preform composite layer on the carbon nanotube layer.

3. The method of claim 1, wherein the applying the vanadium oxide layer on the carbon nanotube layer comprises:

providing a plurality of carbon nanotube films;

depositing a plurality of vanadium oxide layers on a plurality of carbon nanotube films to obtain a plurality of preform composite layers, wherein each of the plurality of vanadium oxide layers is deposited on one of the plurality of carbon nanotube films; and

stacking the plurality of preform composite layers on the carbon nanotube layer.

4. The method of claim 3, wherein the thickness of each of the plurality of carbon nanotube films is less than 30 nanometers, and the thickness of the vanadium oxide layer is greater than 30 nanometers.

5. The method of claim 4, wherein the length of the vanadium oxide layer is less than the length of each of the plurality of carbon nanotube films.

6. The method of claim 5, wherein after obtain the vanadium dioxide layer, a portion of each of the plurality of carbon nanotube films extends out of the vanadium dioxide layer to form an outside portion.

7. The method of claim 6, further comprising making the outside portion be in direct contact with the carbon nanotube layer.

8. The method of claim 7, wherein the making the outside portion be in direct contact with the carbon nanotube layer comprises mechanical pressing or organic solvent treating.

9. The method of claim 1, wherein the applying the vanadium oxide layer on the carbon nanotube layer comprises:

providing a carbon nanotube array, the carbon nanotube comprising a plurality of carbon nanotubes substantially parallel to each other;

expanding spatial separation within the carbon nanotube array along a direction perpendicular to a length direction of the plurality of carbon nanotubes to obtain an expanded carbon nanotube array;

depositing the vanadium oxide layer on the expanded carbon nanotube array to form a preform composite layer, wherein the vanadium oxide layer fills in spaces of the expanded carbon nanotube array; and

stacking the preform composite layer on the carbon nanotube layer.

10. The method of claim 9, wherein the stacking the preform composite layer on the carbon nanotube layer comprises making the plurality of carbon nanotubes perpendicular to the carbon nanotube layer.

11. The method of claim 9, wherein the stacking the preform composite layer on the carbon nanotube layer comprises making each of the plurality of carbon nanotubes having one end in direct contact with the carbon nanotube layer.

12. The method of claim 1, further comprising coating a flexible protection layer on at least one of the carbon nanotube layer and the vanadium dioxide layer.

13. The method of claim 12, wherein the coating the flexible protection layer comprises entirely enveloping both the carbon nanotube layer and the vanadium dioxide layer by the flexible protection layer.

14. The method of claim 1, wherein the applying the vanadium oxide layer on the carbon nanotube layer comprises doping the vanadium oxide layer.

15. The method of claim 14, wherein the vanadium oxide layer is doped with an element selected from the group consisting of tungsten, molybdenum, aluminum, phosphorus, niobium, thallium, and fluorine.