High Surface Area Mixed Oxides Containing Supermicropores

Boris G. Shpeizer, Vanessa Chapa, Amanda Higginbotham, Joy M. Heising and Abraham Clearfield, Texas A&M University,

DMR-0332453In spite of the enormous effort currently in progress to prepare porous materials for use in catalysis, as sorbents and as sensors, there is a dearth of such materials with pores in the 10-20 Å region. We have developed a process by which mixed oxides containing pores in the desired range are routinely achieved. 1 One such family consisting of ZnO-Al2O3-SiO2 in the ratio 0.21:0.053:1 yielded the N2 sorption-desorption isotherms shown in Figure 1. Utilizing amines of increasing chain length as templates the surface areas increased from 431 to 872 m2/g and pore volumes from 0.183 to 0.449 cc/g. Pore size averages ranged from 8 to 12 Å in diameter. These mixed oxides also sorbed H2 up to 3 weight percent at 77K and 1 atm for the one with the largest surface area. Similar families based on titania, zirconia, and lanthana with transition metals have been prepared.

1. Chem. Commun., 2005, 2396-2398. Nitrogen Adsorption/desorption on [ZnO on Al2O3/SiO2] vs. Size of theAmine Employed

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Relative pressure (P/Po)

P ropylamine Butylamine Amylamine Hexylamine

Heptylamine Oc tylamine Oc tadec ylamine

High Surface Area Mixed Oxides Containing Supermicropores

Boris G. Shpeizer, Vanessa Chapa, Amanda Higginbotham, Joy M. Heising and Abraham Clearfield, Texas A&M University,

DMR-0332453Two of the authors, Vanessa Chapa and Amanda Higginbotham, are undergraduates. Vanessa enrolled last year in the graduate program at Texas A&M pursuing an advanced degree in analytical chemistry, and Amanda was accepted into the graduate program at Rice University. She finished with a straight 4.0 grade point average and stood number one in her class. There are nine undergraduates working in the Clearfield research group including four this summer. Two of the undergraduates are Hispanic and two are African-American. This summer, as in the past, we are participating in the Solid State NSF REU program. Dr. Remi Oki and two students from Prairie View A&M University, a historically Black University, are currently working on the mixed oxide program. They have indicated their willingness to continue the research during the coming academic year at Prairie View and we are planning a collaborative program.

Undergraduate research group with Prof. R. Oki, Paul Bonham, and Jesse Onyenekwe from Prairie View A&M University.