Triblock Copolymer Syntheses of Mesoporous Silica with Periodic 50 to 300 Angstrom Pores

American Association for the Advancement of Science (AAAS) - Tập 279 Số 5350 - Trang 548-552 - 1998
Dongyuan Zhao1,2,3, Jianglin Feng2,3, Dan Shao2,3, Nicholas A. Melosh2,3, Glenn H. Fredrickson2,3, Bradley F. Chmelka2,3, Galen D. Stucky2,3
1D. Zhao, Q. Huo, G. D. Stucky, Department of Chemistry and Materials Research Laboratory, University of California, Santa Barbara, CA 93106, USA. J. Feng, Department of Chemistry and Center for Quantized Electronic Structures, University of.
2J. Feng, Department of Chemistry and Center for Quantized Electronic Structures, University of California, Santa Barbara, CA 93106, USA.
3N. Melosh, G. H. Fredrickson, B. F. Chmelka, Materials Research Laboratory and Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA.

Tóm tắt

Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p 6 mm ) silica-block copolymer mesophases. Calcination at 500°C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35° to 80°C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140°C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.

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Supported by NSF under grants DMR-9520971 (G.D.S.) and DMR-9257064 (B.F.C.) the U.S. Army Research Office under grant DAAH04-96-1-0443 and the David and Lucille Packard Foundation (B.F.C.). We made use of UCSB Materials Research Laboratory Central Facilities supported by NSF under award DMR-9632716. B.F.C. is a Camille and Henry Dreyfus Teacher-Scholar and an Alfred P. Sloan Research Fellow. We thank BASF (Mt. Olive NJ) for providing block copolymer surfactants.

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American Association for the Advancement of Science (AAAS)

Tập 279 Số 5350

548-552

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