Sol-gel strategies for pore size control of high-surface-area transition-metal oxide aerogels

Journal Article · Thu Feb 01 04:00:00 EST 1996 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm950407g· OSTI ID:369913

Suh, D J; Park, T J ^[1]

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1. Korea Institute of Science and Technology, Seoul (Korea, Republic of)

Titania, zirconia, and niobia aerogels were prepared by the sol-gel synthesis from alcoholic metal alkoxide solutions under acidic conditions and the subsequent supercritical drying with carbon dioxide. At a stoichiometric amount of the water and a constant alkoxide concentration the nitric acid contents were varied to examine the characteristics of gel formation behavior and the produced aerogels properties. The range of acid content in which transparent polymeric gels were obtained was determined. under these conditions there was little effect of acid content on the surface area of the calcined aerogel samples. On the other hand, the pore size distributions were significantly affected by the acid contents. The resulting titania, zirconia, and niobia aerogels, after calcination at 773 K for 2h, had BET surface areas of about 200, 100, and 200m{sup 2}/g, respectively, and relatively narrow pore size distributions in the mesopore region. The result suggest a simple way to control the pore sizes of the high-surface-area aerogel only by adjusting the amount of nitric acid used in the sol-gel synthesis. 28 refs., 8 figs., 2 tabs.

• OSTI ID: 369913
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 2 Vol. 8; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
CALCINATION
GELS
NIOBIUM OXIDES
NITRIC ACID
PORE STRUCTURE
SOL-GEL PROCESS
SURFACE AREA
TEXTURE
TITANIUM OXIDES
X-RAY DIFFRACTION
ZIRCONIUM OXIDES