Surface-functionalized mesoporous carbon materials
A functionalized mesoporous carbon composition comprising a mesoporous carbon scaffold having mesopores in which polyvinyl polymer grafts are covalently attached, wherein said mesopores have a size of at least 2 nm and up to 50 nm. Also described is a method for producing the functionalized mesoporous composition, wherein a reaction medium comprising a precursor mesoporous carbon, vinyl monomer, initiator, and solvent is subjected to sonication of sufficient power to result in grafting and polymerization of the vinyl monomer into mesopores of the precursor mesoporous carbon. Also described are methods for using the functionalized mesoporous carbon, particularly in extracting metal ions from metal-containing solutions.
1. A functionalized mesoporous carbon composition comprising a mesoporous carbon scaffold having: (i) mesopores in which polyvinyl polymer grafts are covalently attached, and (ii) macropores having a size greater than 50 nm and up to 200 nm, wherein said mesopores have a size of at least 2 nm and up to 50 nm, and said carbon is elemental carbon.
2. The functionalized mesoporous carbon composition of claim 1 , wherein the polyvinyl polymer grafts are comprised of the formula:
wherein R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen atom, hydrocarbon groups having at least 1 and up to 12 carbon atoms, and heteroatom-containing groups comprising at least one heteroatom selected from nitrogen, oxygen, sulfur, and phosphorus; and the subscript n is an integer of at least 2.
3. The functionalized mesoporous carbon composition of claim 2 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a nitrile group.
4. The functionalized mesoporous carbon composition of claim 2 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a heteroatom-containing functional group that can bind to metal ions.
5. The functionalized mesoporous carbon composition of claim 4 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a carboxylate, keto, aldo, amino, imino, amido, or oxime group.
6. The functionalized mesoporous carbon composition of claim 4 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of an amidoxime group.
7. The functionalized mesoporous carbon composition of claim 2 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a negatively-charged group.
8. The functionalized mesoporous carbon composition of claim 7 , wherein said negatively-charged group is a sulfonate or carboxylate group.
9. The functionalized mesoporous carbon composition of claim 2 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is an unsubstituted hydrocarbon group having at least four carbon atoms.
10. The functionalized mesoporous carbon composition of claim 1 , wherein the pore volume due to mesopores is greater than the pore volume due to micropores.
11. A method for fabricating a functionalized mesoporous carbon composition, the method comprising subjecting a reaction medium comprising a precursor mesoporous carbon, vinyl monomer, initiator, and solvent to sonication of sufficient power to result in grafting and polymerization of said vinyl monomer into mesopores of said precursor mesoporous carbon to produce said functionalized mesoporous carbon composition, wherein said mesopores have a size of at least 2 nm and up to 50 nm and wherein said mesoporous carbon scaffold also contains macropores having a size greater than 50 nm and up to 200 nm, and said carbon is elemental carbon.
12. The method of claim 11 , wherein said precursor mesoporous carbon is activated to increase its specific surface area, prior to the precursor mesoporous carbon being included in said reaction medium and subjected to said sonication.
13. The method of claim 11 , wherein said vinyl monomer has the formula:
wherein R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen atom, hydrocarbon groups having at least 1 and up to 12 carbon atoms, and heteroatom-containing groups comprising at least one heteroatom selected from nitrogen, oxygen, sulfur, and phosphorus.
14. The method of claim 13 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a nitrile group.
15. The method of claim 13 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a heteroatom-containing functional group that can bind to metal ions.
16. The method of claim 15 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a carboxylate, keto, aldo, amino, imino, amido, or oxime group.
17. The method of claim 15 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of an amidoxime group.
18. The method of claim 13 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is comprised of a negatively-charged group.
19. The method of claim 18 , wherein said negatively-charged group is a sulfonate or carboxylate group.
20. The method of claim 13 , wherein at least one of R 1 , R 2 , R 3 , and R 4 is an unsubstituted hydrocarbon group having at least four carbon atoms.
21. The method of claim 11 , wherein the pore volume due to said mesopores is greater than the pore volume due to micropores in said functionalized mesoporous carbon composition.
22. A method for extracting metal ions from a liquid solution containing metal ions, the method comprising contacting said liquid solution with a functionalized mesoporous carbon composition comprising a mesoporous carbon scaffold having mesopores in which polyvinyl polymer grafts are covalently attached, wherein at least a portion of said polyvinyl polymer grafts are comprised of heteroatom-containing functional groups that can bind to said metal ions, wherein said mesopores have a size of at least 2 nm and up to 50 nm, and wherein said mesoporous carbon scaffold also contains macropores having a size greater than 50 nm and up to 200 nm, and said carbon is elemental carbon.
23. The method of claim 22 , wherein said heteroatom-containing functional groups are selected from carboxylate, keto, aldo, amino, imino, amido, oxime, and amidoxime groups.
24. The method of claim 22 , wherein said heteroatom-containing functional groups are selected from negatively-charged groups.
25. The method of claim 22 , wherein the polyvinyl polymer grafts are comprised of the formula:
wherein R 1 , R 2 , R 3 , and R 4 are independently selected from hydrogen atom, hydrocarbon groups having at least 1 and up to 12 carbon atoms, and heteroatom-containing groups comprising at least one heteroatom selected from nitrogen, oxygen, sulfur, and phosphorus; and the subscript n is an integer of at least 2.
26. The method of claim 22 , wherein the pore volume due to said mesopores is greater than the pore volume due to micropores in said functionalized mesoporous carbon composition.
27. The method of claim 22 , wherein said metal ions are selected from transition, lanthanide, and actinide metal ions.