Continuous graphitic fibers from living graphene molecules
A unitary graphene-based continuous graphitic fiber comprising at least 90% by weight of graphene planes that are chemically bonded with one another having an inter-planar spacing from 0.3354 to 0.4 nm and an oxygen content of 0.01 to 5% by weight, wherein the graphene planes are parallel to one another and parallel to a fiber axis direction and the graphitic fiber contains no core-shell structure, have no helically arranged graphene domains, and have a porosity level less than 5% by volume. This fiber can be produced by a continuous filament of graphene oxide gel having living graphene oxide molecules or functionalized graphene chains dissolved in a fluid medium. The filament is deposited onto a supporting substrate under a molecule-aligning stress condition along the filament axis direction and then subjected to drying and heating treatments.
1. A unitary graphene-based continuous graphitic fiber having an inter-planar spacing d 002 from 0.3354 nm to 0.4 nm as determined by X-ray diffraction and an oxygen content of 0.001 to 5% by weight, wherein said graphene planes are parallel to one another and parallel to a fiber axis direction and said graphitic fiber contains no core-shell structure and no helically arranged graphene domains, wherein said unitary graphitic fiber is a single crystal or a poly-crystal graphene structure that has a thickness greater than 100 nm, a physical density no less than 1.7 g/cm 3 , an electrical conductivity from 3,000 S/cm to 20,000 S/cm and a thermal conductivity from 600 W/mK to 1,805 W/mK, and said unitary graphene material has a preferred crystalline orientation, wherein said graphene planes are closely packed and parallel to one another.
2. The continuous graphitic fiber of claim 1 , wherein said inter-plane spacing d 002 is from 0.3354 nm to 0.36 nm and the oxygen content is from 0.01 to 2% by weight.
3. The continuous graphitic fiber of claim 1 , having a cross-section that is circular, elliptical, rectangular, flat-shaped, or hollow.
4. The continuous graphitic fiber of claim 1 , having a diameter or thickness from 10 μm to 100 μm.
5. The continuous graphitic fiber of claim 1 , having a diameter or thickness less than 10 μm.
6. The continuous graphitic fiber of claim 1 , having a diameter or thickness less than 1 μm.
7. The continuous graphitic fiber of claim 1 , having a diameter or thickness less than 100 nm.
8. The continuous graphitic fiber of claim 1 , having an oxygen content from 0.001 to 1% by weight, an inter-graphene spacing less than 0.345 nm, a thermal conductivity from 1,000 W/mK to 1,700 W/mK and/or an electrical conductivity from 2,000 S/cm to 12,000 S/cm.
9. The continuous graphitic fiber of claim 1 , having an oxygen content from 0.001% to 0.01%, an inter-graphene spacing less than 0.337 nm, a thermal conductivity from 1,000 W/mK to 1,700 W/mK, and/or an electrical conductivity from 4,500 S/cm to 12,000 S/cm.
10. The continuous graphitic fiber of claim 1 , having an oxygen content no greater than 0.001%, an inter-graphene spacing less than 0.336 nm, a mosaic spread value no greater than 0.7, a thermal conductivity from 1,000 W/mK to 1,805 W/mK, and/or an electrical conductivity from 7,000 S/cm to 12,000 S/cm.
11. The continuous graphitic fiber of claim 1 , having an inter-graphene spacing less than 0.336 nm, a mosaic spread value no greater than 0.4, a thermal conductivity from 1,700 W/mK to 1,805 W/mK, and/or an electrical conductivity greater than 12,000 S/cm.
12. The continuous graphitic fiber of claim 1 , wherein the continuous graphitic fiber exhibits an inter-graphene spacing less than 0.337 nm and a mosaic spread value less than 1.0.
13. The continuous graphitic fiber of claim 1 , wherein the continuous graphitic fiber exhibits a degree of graphitization no less than 40% and/or a mosaic spread value less than 0.7.
14. The continuous graphitic fiber of claim 1 , wherein the continuous graphitic fiber exhibits a degree of graphitization no less than 80% and/or a mosaic spread value no greater than 0.4.
15. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber contains chemically bonded graphene molecules or chemically merged graphene planes that are parallel to one another.
16. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber contains a first graphene domain containing bonded graphene planes parallel to one another and having a first crystallographic c-axis, and a second graphene domain containing bonded graphene planes parallel to one another and having a second crystallographic c-axis wherein the first crystallographic c-axis and the second crystallographic c-axis are inclined with respect to each other at an angle less than 10 degrees.
17. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber contains no complete grain boundary therein, is a graphite single crystal, or a poly-crystal graphite structure with graphene molecules being oriented along a fiber axis direction.
18. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber is a poly-crystal graphitic structure having a grain size from 1 μm to 10 μm.
19. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber is a poly-crystal graphitic structure having a grain size from 10 μm to 100 μm.
20. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber is a poly-crystal graphitic structure having a grain size larger than 100 μm.
21. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber contains a combination of sp 2 and sp 3 electronic configurations.
22. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber has a physical density greater than 1.7 g/cm 3 , a Young's modulus greater than 60 GPa, and/or a tensile strength greater than 1.2 GPa.
23. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber has an electrical conductivity greater than 5,000 S/cm, a thermal conductivity from 1,000 W/mK to 1,805 W/mK, a physical density greater than 1.8 g/cm 3 , a Young's modulus greater than 200 GPa, and/or a tensile strength greater than 3.2 GPa.
24. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber has an electrical conductivity greater than 15,000 S/cm, a thermal conductivity from 1,500 W/mK to 1,805 W/mK, a physical density greater than 1.9 g/cm 3 , a Young's modulus greater than 300 GPa, and/or a tensile strength greater than 5.0 GPa.
25. The continuous graphitic fiber of claim 1 , wherein said continuous graphitic fiber has an electrical conductivity greater than 18,000 S/cm, a thermal conductivity from 1,700 W/mK to 1,805 W/mK, a physical density greater than 1.9 g/cm 3 , a Young's modulus greater than 600 GPa, and/or a tensile strength measured greater than 8.0 GPa.
26. A fiber yarn or bundle comprising at least a continuous graphitic fiber of claim 1 .
27. A fiber yarn or bundle comprising multiple continuous graphitic fibers of claim 1 .