Professors Mary K. Carroll (Chemistry) and Ann M. Anderson (Mechanical Engineering) of Union College are supported by the Analytical and Surface Chemistry Program in the Division of Chemistry to prepare and characterize aerogels - porous nanostructured materials that are approximately 90-99% air by volume. An interdisciplinary team of faculty and undergraduate students is working to (1) develop a fundamental understanding of how changes in the novel rapid supercritical extraction (RSCE) method used to prepare aerogels affects the resulting properties, and (2) demonstrate the utility of tailored RSCE aerogel materials for specific applications including optical chemical sensing, chemical spill clean-up, and the development of low drag hydrophobic surfaces and thermal insulating materials.
In addition to potential contributions to society from development of novel materials , the work achieves broader impact by supporting opportunities for undergraduate students in exciting cross-disciplinary research. The team is part of the Converging Technologies (CT) initiative at Union College, which brings together students and faculty from engineering and the liberal arts to examine problems that occur at the intersections of traditional disciplines. Undergraduate students in chemistry, biochemistry and mechanical engineering as well as high-school students are engaged in aerogel research at Union, working alongside faculty mentors, using state-of-the-art instrumentation, presenting and, in some cases, publishing their results.
This grant supported research on aerogel materials by an interdisciplinary team in the Chemistry and Mechanical Engineering Departments at Union College. Aerogels are solids that have unusual properties, including very low density and very high surface area, which make them attractive for a wide range of applications. The research team had previously developed a novel rapid supercritical extraction method for preparing aerogels. In this project, the team extended their work to include studies that aimed to develop a fundamental understanding of the effect of aerogel precursor chemistry on the properties of the resulting aerogel materials, and to demonstrate how the aerogels could be used in specific applications. By varying the starting materials and processing conditions used, the Union College team successfully prepared and characterized several types of aerogels via the rapid supercritical method. These include silica aerogels for applications in insulation and gas sensors, hydrophobic silica aerogels for drag reduction and chemical-spill clean-up, titania and titania-silica aerogels for photocatalysis applications, and alumina-based aerogels for catalytic remediation of automotive exhaust. The Union College researchers used a variety of physical characterization methods to determine the density, surface area, spectroscopic and structural properties of the materials, as well as their suitability for the specific applications. The aerogels prepared via the rapid method have comparable properties to materials prepared by conventional methods, which generally are more time-consuming and generate considerable chemical waste. In the long term, there is significant potential for society to benefit from the development of novel materials for thermal insulation, chemical spill clean-up, catalysis and sensing applications, prepared via a rapid process that generates relatively little waste. The project had an immediate impact on the scientific infrastructure of the US: the introduction of undergraduate students to cross-disciplinary research at a formative stage of their education. Students participated in all aspects of the research – from experimental work to data analysis to presentation at regional and national meetings to publication in the scientific literature. Over the four-year funding period, 31 different students participated in this grant-funded research at Union College: 29 undergraduate chemistry, biochemistry and mechanical engineering students, 2 masters-degree students, and 1 high-school student. These include 14 female students, 4 students from groups underrepresented in STEM fields, and 6 international students. Of the 18 students who completed their undergraduate degrees during this time period, 8 have continued on to graduate school in science or engineering, 1 went to medical school, 6 to entry-level jobs in STEM fields, and 1 to Teach for America. Both of the masters-degree students (one of whom continued in the lab after earning a BS from Union) are now enrolled in doctoral programs in engineering, and the high-school student is now an undergraduate chemical engineering major at a four-year university.
