Synthesis of Silver Nanostructures with Controlled Shapes and Properties

Benjamin J. Wiley was born in Rochester, NY, in 1981. He received a B.S. degree in chemical engineering from the University of Minnesota in 2003 and a Ph.D. degree in chemical engineering from the University of Washington (under the guidance of Professor Younan Xia) in 2007. He is currently working as a postdoctoral fellow with Professor George M. Whitesides at Harvard University. His research interests include the modification of material properties through control over nanostructure, microstructure, and surface chemistry, as well as how such control can be applied toward the improvement of human health.

Yugang Sun was born in Shangdong, China, in 1975. He received his B.S. and Ph.D. degrees in chemistry from the University of Science and Technology of China (USTC) in 1996 and 2001, respectively. He worked as a postdoctoral research associate with Professor Younan Xia at the University of Washington until 2003 and with Professor John Rogers at the University of Illinois at Urbana–Champaign until 2006. He is now a staff scientist at the Argonne National Laboratory. His research interests include synthesis and characterization of nanostructures, micro/nanofabrication, bioanalysis, and devices for photonics and electronics.

Younan Xia was born in Jiangsu, China, in 1965. He received a B.S. degree in chemical physics from the University of Science and Technology of China (USTC) in 1987 and then worked as a graduate student on nonlinear optical materials for 4 years at the Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences. He came to the United States in 1991, received a M.S. degree in inorganic chemistry from the University of Pennsylvania (with Professor Alan G. MacDiarmid) in 1993, and a Ph.D. degree in physical chemistry from Harvard University (with Professor George M. Whitesides) in 1996. He then worked as a postdoctoral fellow with Professors George M. Whitesides and Mara Prentiss. He moved to Seattle in 1997 and started as an Assistant Professor of Chemistry at the University of Washington. He was promoted to Associated Professor and Professor in 2002 and 2004, respectively. His research interests include nanostructured materials, nanomedicine, biomaterials, self-assembly, photonic crystals, colloidal science, microfabrication, surface modification, and electrospinning.

Mastery over the shape of a nanostructure enables control over its properties and usefulness for a given application. By controlling the crystallinity of the seeds from which nanostructures grow and the rate of atomic addition to seeds, we selectively produced pentagonal nanowires, cuboctahedra, nanocubes, nanobars, bipyramids, and nanobeams of silver with a solution-phase polyol synthesis. The example of nanobars illustrates how the shape of a silver nanostructure affects the color of light that it scatters. We further show how silver nanowires and nanobeams can serve as conduits for both electrons and photons.