FIBRILLAR CARBON-SILICON COMPOSITE MATERIALS AND METHODS OF MANUFACTURE THEREOF
Carbon-silicon compositions including nanofibrillar carbon networks coated with porous interconnected silicon and their manufacture and use thereof are provided. Embodiments include a composite material including a nanoporous carbon-based scaffold and a silicon-based material. The nanoporous carbon-based scaffold includes a pore structure that includes a fibrillar morphology, where the silicon-based material is contained in the pore structure. The compositions find utility in various applications, including electrical energy storage electrodes and devices comprising the same.
1 . A carbon-silicon composition comprising: a composite material including a nanoporous carbon-based scaffold and a silicon-based material, the nanoporous carbon-based scaffold comprising a pore structure, the pore structure comprising a fibrillar morphology, wherein the silicon-based material is contained in the pore structure of the nanoporous carbon-based scaffold.
2 . The carbon-silicon composition of claim 1 , wherein the nanoporous carbon-based scaffold comprises a carbon aerogel.
3 - 4 . (canceled)
5 . The carbon-silicon composition of claim 1 , wherein the silicon-based material is in the form of nanoparticles dispersed on the surface of the pore structure.
6 . (canceled)
7 . The carbon-silicon composition of claim 5 , wherein the nanoparticles have at least one dimension in the range of about 5 nm to about 20 nm.
8 . (canceled)
9 . The carbon-silicon composition of claim 1 , wherein the silicon-based material is in the form of a layer on the surface of the pore structure.
10 . (canceled)
11 . The carbon-silicon composition of claim 9 , wherein the thickness of the layer is in the range of about 5 nm to about 20 nm.
12 . (canceled)
13 . The carbon-silicon composition of claim 1 , wherein the pore structure comprises less than 30% micropores, less than 30% macropores, greater than 50% mesopores and a total pore volume greater than 0.1 cc/g.
14 . The carbon-silicon composition of claim 1 , wherein the pore structure comprises less than 20% micropores, less than 20% macropores, greater than 70% mesopores and a total pore volume greater than 0.1 cc/g.
15 . The carbon-silicon composition of claim 1 , wherein the pore structure comprises less than 10% micropores, less than 10% macropores, greater than 80% mesopores and a total pore volume greater than 0.1 cc/g.
16 . The carbon-silicon composition of claim 1 , wherein the composite material includes a porous interconnected silicon coated fibrillar carbon network.
17 . (canceled)
18 . (canceled)
19 . A method for preparing a carbon-silicon composition, the process comprising:
providing a nanoporous carbon-based scaffold comprising a pore structure, the pore structure comprising a fibrillar morphology; and
heating the nanoporous carbon-based scaffold at an elevated temperature in the presence of a silicon-containing gas to impregnate silicon within the pore structure of the nanoporous carbon-based scaffold.
20 . The method of claim 19 , wherein the silicon impregnated within the pore structure of the nanoporous carbon-based scaffold is nano sized, and resides within pores formed by the fibrillar morphology.
21 . The method of claim 19 , wherein the carbon-silicon composition includes a porous interconnected silicon coated fibrillar carbon network.
22 - 24 . (canceled)
25 . The method of claim 19 , further comprising providing a polyimide precursor, initiating imidization of the polyimide precursor chemically or thermally; combining the polyimide precursor with a medium that is non-miscible with the polyimide precursor, thereby forming droplets of the imidized polyimide; drying the droplets of the polyimide to yield a particulate porous polyimide material; and carbonizing the particulate porous polyimide material to provide the nanoporous carbon-based scaffold.
26 . The method of claim 19 , wherein the pore structure comprises less than 30% micropores, less than 30% macropores, greater than 50% mesopores and a total pore volume greater than 0.1 cc/g.
27 . The method of claim 19 , wherein the pore structure comprises less than 20% micropores, less than 20% macropores, greater than 70% mesopores and a total pore volume greater than 0.1 cc/g.
28 . The method of claim 19 , wherein the pore structure comprises less than 10% micropores, less than 10% macropores, greater than 80% mesopores and a total pore volume greater than 0.1 cc/g.
29 . An energy storage device comprising the carbon-silicon composition of claim 1 .
30 . The energy storage device of claim 29 , wherein the energy storage device is a lithium-ion battery.