When
Presenter: Dr. Catherine J. Murphy Larry R. Faulkner Endowed Chair in Chemistry, and Head, Department of Chemistry University of Illinois Urbana-Champaign
Abstract: In the 5-100 nm size range, colloidal gold and silver nanocrystals exhibit brilliant shape-dependent optical properties that enable applications in chemical sensing, biological imaging, optical displays, enhanced energy conversion devices, mechanically improved polymer nanocomposites and photothermal therapy for thermal ablation of pathogenic cells. It is now well-known that plasmons, coherent oscillations of the conduction band electrons in metals upon resonant illumination, are responsible for these brilliant colors. While it is relatively easy to image the gold core by transmission electron microscopy, it is far more difficult to gain deep knowledge of the organic ligands that surround the nanocrystals in colloidal solution. Described in this talk are experiments to quantify average ligand density and dynamics on gold nanocrystals as a function of nanocrystal size by NMR; individual nanocrystal ligand density mapping by STEM/EELS; and general results in the catalysis space and the biological space that illustrate the importance of the “soft shell” around hard inorganic nanocrystals.
Bio Sketch: Catherine J. Murphy is the Larry R. Faulkner Endowed Chair in Chemistry and current Head of the Department of Chemistry at Illinois. She earned two B.S. degrees at Illinois in 1986, one in chemistry and one in biochemistry. She performed organometallic undergraduate research with Tom Rauchfuss at Illinois. Murphy went to graduate school at the University of Wisconsin, Madison, working with Art Ellis on single-crystal semiconductor surface chemistry; she earned her Ph.D. in 1990. From 1990-1993, she was an NSF and then an NIH postdoctoral fellow in the laboratory of Jackie Barton at Caltech. From 1993-2009, she was on the faculty of chemistry and biochemistry at the University of South Carolina. In 2009 she was recruited back home to Illinois to join the chemistry faculty. Murphy’s honors include the 2022 Centenary Prize of the Royal Society of Chemistry, the 2020 American Chemical Society (ACS) Award in Inorganic Chemistry, the 2019 Remsen Award, the 2019 Linus Pauling Medal, the 2019 MRS Medal, the 2013 Carol Tyler Award of the International Precious Metals Institute, and the 2011 ACS Division of Inorganic Chemistry’s Inorganic Nanoscience Award. She has been named a Nanotech Briefs Nano 50 Innovator (2008), a Camille Dreyfus Teacher-Scholar (1998), an Alfred P. Sloan Research Fellow (1997), a Cottrell Scholar of the Research Corporation(1996) and an NSF CAREER Award winner (1995). She is a Fellow of the American Chemical Society, the Materials Research Society, the Royal Society of Chemistry, and of the American Association for the Advancement of Science. She was ranked #32 in Thomson Reuters Sciencewatch List of “Top 100 Chemists for the Decade 2000-2010” and #10 on their list of “Top 100 Materials Scientists of the Decade 2000-2010.” In 2015, she was elected to the U.S. National Academy of Sciences and in 2019, she was elected to the American Academy of Arts and Sciences.
Host: Dr. Vanessa Huxter