Boron nitride and method of producing boron nitride
BN nanosheets are prepared by a method comprising heating to a temperature of at least 500° C., a mixture comprising: (1) an alkali borohydride, and (2) an ammonium salt. NaN 3 may be included to increase the yield. No catalyst is required, and the product produced contains less than 0.1 atomic percent metal impurities.
1. h-BN nanosheets,
wherein the h-BN nanosheets contain less than 0.1 atomic percent metal impurities and have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 002 peak of at most 0.50 degrees,
the h-BN nanosheets have an aspect ratio of at least 10:1, and
the h-BN nanosheets are not nanofibers.
2. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets are few layer h-BN nanosheets.
3. The h-BN nanosheets of claim 2 , wherein the h-BN nanosheets have 6 to 20 layers of BN.
4. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets do not contain r-BN, as determined by X-ray powder diffraction.
5. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 002 peak of at most 0.30 degrees.
6. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.50 degrees.
7. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.25 degrees.
8. The h-BN nanosheets of claim 1 , wherein the h-BN nanosheets have a particle size of 250 to 900 nm.
9. A capacitor, comprising:
(a) a substrate,
(b) a first conductive layer, on the substrate
(c) an insulating layer, on the conductive layer, and
(d) a second conductive layer, on the insulating layer,
wherein the insulating layer comprises the h-BN nanosheets of claim 1 .
10. The capacitor of claim 9 , wherein the h-BN nanosheets are few layer h-BN nanosheets.
11. The capacitor of claim 9 , wherein the h-BN nanosheets have 6 to 20 layers of BN.
12. The capacitor of claim 9 , wherein the h-BN nanosheets do not contain r-BN, as determined by X-ray powder diffraction.
13. The capacitor of claim 9 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 002 peak of at most 0.30 degrees.
14. The capacitor of claim 9 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.50 degrees.
15. The capacitor of claim 9 , wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.25 degrees.
16. The h-BN nanosheets of claim 1 ,
wherein the h-BN nanosheets have 6 to 20 layers of BN,
the h-BN nanosheets do not contain r-BN, as determined by X-ray powder diffraction, and
the h-BN nanosheets have a particle size of 250 to 900 nm.
17. The h-BN nanosheets of claim 1 ,
wherein the h-BN nanosheets have 6 to 20 layers of BN, and
the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.25 degrees.
18. The h-BN nanosheets of claim 1 ,
wherein the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 002 peak of at most 0.30 degrees, and
the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.25 degrees.
19. The capacitor of claim 9 ,
wherein the h-BN nanosheets have 6 to 20 layers of BN,
the h-BN nanosheets do not contain r-BN, as determined by X-ray powder diffraction, and
the h-BN nanosheets have a particle size of 250 to 900 nm.
20. The capacitor of claim 9 ,
wherein the h-BN nanosheets have 6 to 20 layers of BN, and
the h-BN nanosheets have a full width at half maximum (FWHM) of the X-ray powder diffraction pattern for a d 100 peak of at most 0.25 degrees.