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Synthesis and Characterization of Copper-Nanoparticle-Containing Silica Aerogel Prepared via Rapid Supercritical Extraction for Applications in Three-Way Catalysis

Published online by Cambridge University Press:  11 May 2017

Ann M. Anderson*
Affiliation:
Department of Mechanical Engineering, Union College, Schenectady, NY 12302 USA
Elizabeth A. Donlon
Affiliation:
Department of Mechanical Engineering, Union College, Schenectady, NY 12302 USA
Adam A. Forti
Affiliation:
Department of Mechanical Engineering, Union College, Schenectady, NY 12302 USA
Vinicius P. Silva
Affiliation:
Department of Mechanical Engineering, Union College, Schenectady, NY 12302 USA
Bradford A. Bruno
Affiliation:
Department of Mechanical Engineering, Union College, Schenectady, NY 12302 USA
Mary K. Carroll
Affiliation:
Department of Chemistry Union College, Schenectady, NY 12302 USA
*
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Abstract

Copper-alumina and copper-silica aerogels formed by impregnation of a copper(II) salt into an alumina or silica wet gel before supercritical extraction have been found to contain copper in multiple oxidation states: Cu0, Cu+1 and Cu+2. These aerogels are effective at catalyzing the reduction of NO and the oxidation of HCs and CO under conditions similar to those found in automotive three way catalysts. In this work we have developed a preparation method incorporating Cu0, Cu+1 and Cu+2 nanoparticles directly into silica aerogels. Nanoparticles in the form of (a) Cu0 nanorods (100 nm diameter, 10-20 μm length); (b) Cu+1 nanoparticles (350 nm diameter); and (c) Cu+2 nanoparticles (25-55 nm diameter) were added (0.5-15% by weight) to separate precursor mixtures consisting of tetramethyl orthosilicate, methanol, water and ammonia. These precursor mixtures were then processed using a rapid supercritical extraction (RSCE) method to form aerogels. The resulting aerogels show evidence of nanoparticles dispersed throughout the silica aerogel structure. Addition of Cu+1 and Cu+2 nanoparticles decreases the surface area of the aerogels significantly. X-Ray diffraction shows that regardless of initial oxidation state of the nanoparticles, crystalline Cu0 is detected after RSCE processing to 290 °C. Following heat treatment at 700 °C, crystalline Cu+2 is detected. The copper containing silica aerogels are found to be catalytically active with light-off temperatures (50% conversion) for NO and CO at 400 °C in three-way catalytic applications.

Type
Articles
Copyright
Copyright © Materials Research Society 2017 

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References

REFERENCES

Juhl, S.J., Dunn, N.J., Carroll, M.K., Anderson, A.M., Bruno, B.A., Madero, J.E., Bono, M.S., J Non-Cryst Solids, 426, 141149 (2015).Google Scholar
Bouck, R.M., Anderson, A.M., Prasad, C., Hagerman, M.E., Carroll, M.K., J Non-Cryst Solids, 453, 94102 (2016).Google Scholar
Bruno, B.A., Madero, J.E., Juhl, S.J., Rodriguez, J., Dunn, N.J., Carroll, M.K., Anderson, A.M., Proc 9th Int‘l Congress on Catalysis and Automotive Pollution Control (CAPoC9), Brussels, (2012).Google Scholar
Smith, L.C., Anderson, A.M., Carroll, M.K., J Sol-Gel Sci Technol, 77, 160171 (2016).Google Scholar
Bruno, B.A., Anderson, A.M., Carroll, M.K., Brockmann, P., Swanton, T., Ramphal, I.A., Palace, T., SAE Technical Paper 2016-01-920, (2016).Google Scholar
Tobin, Z.M., Posada, L.F., Bechu, A.M., Carroll, M.K., Bouck, R.M., Anderson, A.M., Bruno, B.A., in press J Sol-Gel Sci Technol (2017).Google Scholar
Pajonk, G.M., Catal Today, 35, 319337 (1997).Google Scholar
Gauthier, Ben M., Anderson, A.M., Bakrania, S.D., Mahony (Carroll), M.K., Bucinell, R.B., US Patent No. 7,384,988 (10 June 2008).Google Scholar
Gauthier, Ben M., Anderson, A.M., Bakrania, S.D., Mahony (Carroll), M.K., Bucinell, R.B., US Patent No. 8,080,591 (20 December 2011).Google Scholar
Gauthier, B.M., Bakrania, S.D., Anderson, A.M., Carroll, M.K., J Non-Cryst Solids, 350, 238243 (2004).Google Scholar
Carroll, M.K., Anderson, A.M., Gorka, C.A., J Vis. Exp, 84, (2014).Google Scholar
Reichenauer, G., Scherer, G.W., J Non-Cryst Solids, 285, 167174 (2001).Google Scholar
Anderson, A.M., Wattley, C.W., Carroll, M.K., J Non-Cryst Solids, 355, 101–8 (2009).Google Scholar
Xu, W., Du, A., Tang, J., Yan, P., Li, X., Zhang, Z., Shen, J., Zhou, B., RSC Advances, 4, 4954149546 (2014).Google Scholar