Boron nitride converted carbon fiber
This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.
1. A method comprising:
(a) providing boron oxide and carbon fiber, the carbon fiber having a circular cross-section;
(b) heating the boron oxide to melt the boron oxide and heating the carbon fiber;
(c) mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide; and
(d) converting a portion of the carbon fiber proximate a perimeter of the circular cross-section of the carbon fiber to boron nitride, the boron nitride having a thickness of about 10 nanometers to 1.5 microns.
2. The method of claim 1 , wherein the boron oxide and the carbon fiber are heated to about 1000° C. to 2000° C.
3. The method of claim 1 , wherein the boron oxide and the carbon fiber are heated to about 1500° C. to 2000° C.
4. The method of claim 1 , wherein the carbon fiber is heated to a higher temperature than the boron oxide.
5. The method of claim 1 , wherein operations (b), (c), and (d) occur over a time period of about 30 minutes to 120 minutes.
6. The method of claim 1 , wherein the nitrogen-containing gas includes nitrogen.
7. The method of claim 1 , wherein the nitrogen-containing gas includes nitrogen, and wherein a ratio of a partial pressure of boron oxide to a partial pressure of nitrogen is about 1 to 2 during operation (d).
8. The method of claim 1 , wherein a pressure is about 1 bar during operation (d).
9. The method of claim 1 , wherein the carbon fiber is in a form comprising a woven cloth including the carbon fiber.
10. The method of claim 1 , wherein the boron oxide and the carbon fiber are separated from one another during operations (b), (c), and (d).
11. A structure
comprising: a carbon fiber core; and
a boron nitride layer surrounding the carbon fiber core, the boron nitride layer having the same surface morphology as the carbon fiber core, the boron nitride layer having a thickness of about 10 nanometers to 1.5 microns.
12. The structure of claim 11 , wherein the boron nitride layer is not coated onto the carbon fiber core.
13. The structure of claim 11 , wherein the carbon fiber core has a diameter of about 5 microns to 20 microns.
14. The structure of claim 11 , wherein the boron nitride layer has a uniform thickness.
15. The structure of claim 11 , wherein the structure has a color selected from a group consisting of red, green, blue, and variations thereof.
16. The structure of claim 11 , wherein the structure has a color other than black.
17. A
structure comprising: a
carbon fiber core; and
a boron nitride layer surrounding the carbon fiber core, the structure having a color selected from a group consisting of red, green, blue, and variations thereof, the color being determined by a thickness of the boron nitride layer.
18. The structure of claim 17 , wherein the boron nitride layer causes constructive interference of visible light between an outer surface of the boron nitride layer and a surface the carbon fiber core.
19. The structure of claim 17 , wherein the boron nitride layer has a thickness of about 10 nanometers to 1.5 microns.
20. The structure of claim 17 , wherein the carbon fiber core has a diameter of about 5 microns to 20 microns.