MRS Bulletin


Recent Developments in Carbon Nanotube Sorting and Selective Growth

Jie Liu and Mark C. Hersam


Due to their high carrier mobilities, electromigration resistance, and tailorable optical properties, carbon nanotubes are promising candidates for high-performance electronic and optoelectronic applications. However, traditional synthetic methods have lacked control over the structure and properties of carbon nanotubes. This polydispersity problem has confounded efforts to take carbon nanotubes from the research laboratory to the marketplace, especially for electronic and optoelectronic applications, where reliable and reproducible performance is paramount. In recent years, the research community has devoted significant effort to this issue, leading to substantial advances in the preparation of monodisperse carbon nanotube materials. This article highlights the most recent and promising developments from two perspectives: post-synthetic sorting and selective growth of carbon nanotubes of predetermined physical and electronic structure. These complementary approaches have yielded improved uniformity in carbon nanotube materials, resulting in impressive advances in carbon nanotube electronic and optoelectronic technology.

Jie Liu can be reached at the Department of Chemistry, Duke University, Durham, NC 27708, USA; and e-mail

Liu is the Jerry G. and Patricia Crawford Hubbard Professor of Chemistry at Duke University. He earned a BS degree in chemistry from Shandong University in 1987 and a PhD degree in chemistry from Harvard University in 1996. Liu's research interests include synthesis and chemical functionalization of nanomaterials, nanoelectronic devices, scanning probe microscopy, and carbon nanomaterials. As a faculty member, Liu has received the DuPont Young Professor Award, the Outstanding Oversea Young Investigator Award from the National Science Foundation-China, the Ralph E. Powe Junior Faculty Enhancement Award from Oak Ridge Associated Universities, and the Bass Professorship from Duke University for excellence in teaching and research.

Mark C. Hersam can be reached at the Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208-3108, USA; and e-mail

Hersam is a professor of materials science and engineering and a professor of chemistry at Northwestern University. He earned a BS degree in electrical engineering from the University of Illinois at Urbana-Champaign (UIUC) in 1996, a MPhil degree in physics from the University of Cambridge in 1997, and a PhD degree in electrical engineering from UIUC in 2000. Hersam's research interests include nanofabrication, scanning probe microscopy, semiconductor surfaces, and carbon nanomaterials. As a faculty member, Hersam has received several awards, including the Beckman Young Investigator Award, a National Science Foundation CAREER Award, an Army Research Office Young Investigator Award, an Office of Naval Research Young Investigator Award, Sloan Research Fellowship, Presidential Early Career Award for Scientists and Engineers, The Minerals, Metals and Materials Society's Robert Lansing Hardy Award, the American Vacuum Society's Peter Mark Award, three Teacher of the Year awards, and the MRS Outstanding Young Investigator Award.