CAREER: Rational Synthesis and Studies of Functionalized Carbon Nanotubes Stanislaus S. Wong, SUNY at Stony Brook, DMR Probing order in nanotube systems is of fundamental importance in devising applications of these tubes in field emission applications as well as for components of composite materials. We used near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to qualitatively and quantitatively study degree of order and alignment in a wide range of carbon nanotube-based systems, including single-walled carbon nanotube (SWNT) powder, SWNT films, aligned multi-walled carbon nanotubes (MWNTs), and arrays of SWNTs and MWNTs. The results are compared to analogous data obtained from a highly ordered pyrolytic graphite (HOPG) sample.

We have developed an ozonolysis protocol that purifies carbon nanotubes by removing amorphous carbon and metal impurities. In addition, ozonolysis provides a new means for generalizing traditional chemistry to nanotube sidewalls, defect sites, and surfaces. We have recently begun developing a synchrotron-based technique (NEXAFS) as a means of characterizing nanoscale samples, such as carbon nanotubes. (a). NEXAFS spectroscopy is shown to be a useful probe for the investigation of order and alignment in nanotube arrays and composites. In contrast to nanotube powders, SWNT buckypaper and MWNTs arrays on Pt have been studied as model systems to investigate the angular dependence of their sidewall π* intensities. The results are compared to that of HOPG graphite. A quantitative evaluation of order is also presented. Our orientation parameters derived from NEXAFS measurements allowed for the evaluation of relative sample anisotropy in different nanotube- based systems. Ref.: Sarbajit Banerjee †, Tirandai Hemraj-Benny †, Sharadha Sambasivan, Daniel A. Fischer, James A. Misewich, and Stanislaus S. Wong, invited contribution (George W. Flynn’s Festschrift issue). J. Phys. Chem. B, 109(17), (2005). (b). The current study pertains to the analysis of the surface order of vertically-aligned single-walled and multi-walled carbon nanotube arrays of varying length and composition by means of NEXAFS. Both NEXAFS and scanning electron microscopy (SEM) studies concluded that the nanotubes in these samples were oriented vertically to the plane of the surface. However, NEXAFS polarization analysis provided for a more quantitative and nuanced description of the surface structure, indicative of far less localized surface order, an observation partially attributed to misalignment and bending of the tubes. Moreover, it was demonstrated by NEXAFS that the surface order of the arrays was imperfect and relatively independent of the height of the nanotube arrays. In addition, we have shown that NEXAFS can be used to correlate the extent of chemical functionalization and oxygenation with disruption of the electronic and physical structure of nanotubes embedded in array motifs. Ref.: Tirandai Hemraj-Benny et al., “Imperfect Surface Order and Functionalization in Vertical Carbon Nanotube Arrays Probed by Near Edge X-ray Absorption Fine Structure Spectroscopy (NEXAFS)”, invited contribution, Phys. Chem. Chem. Phys., in press. CAREER: Rational Synthesis and Studies of Functionalized Carbon Nanotubes Stanislaus S. Wong, SUNY at Stony Brook, DMR

Education: - Two undergraduates (W. Zaman and H. Gerardi), a high school student (S. Hu), and five graduate students (T. Hemraj-Benny, Y. Mao, H. Zhou, F. Zhang, and T-J. Park) contributed substantially to this work and related projects. S. Banerjee (Ph.D. ‘04) also was a key contributor. - Zaman received an undergraduate research and creative activities (URECA) scholarship (Stony Brook). Hu was granted a Simons fellowship for work in my laboratory. - Gerardi obtained a 2006 Battelle-WISE fellowship for work at Brookhaven National Laboratory. - Mao earned recognition as recipient of the Lee G. Myers award (2006) for Outstanding Doctoral Student (Department of Chemistry). Outreach: - Hosted Daryl Wong on a 2006 DOE Summer Undergraduate Laboratory Internship (SULI). In his project, he used NSF-funded facilities and supplies. - Hosted Megan Johnson (Whittier College) on a 2006 NSF-funded REU scholarship to work on nanotubes and probe microscopy. - Primary organizer: Chemistry Research Day. CAREER: Rational Synthesis and Studies of Functionalized Carbon Nanotubes Stanislaus S. Wong, SUNY at Stony Brook, DMR

Two undergraduates (W. Zaman and H. Gerardi) and six graduate students (Sarbajit Banerjee, Tirandai Hemraj, Yuanbing Mao, Tae Jin Park, Hongjun Zhou, and Fen Zhang) contributed to the work presented. Banerjee and Hemraj-Benny participated in NEXAFS and NEXAFS/silylation experiments, respectively. Zaman was involved with nanotube arrays, and Gerardi performed large scale chemical functionalization procedures, associated with optimizing ozonolysis conditions. She was also involved in spectroscopic analyses of samples. Mao, Zhou, Zhang, and Park worked on an off-shoot of these efforts towards understanding the chemistry and physics of non-carbon nanomaterials, including ternary metal oxide nanostructures. One of the PI’s outreach initiatives was to generate added intellectual exposure to BNL facilities for graduate and undergraduate students. The PI hosted Daryl Wong (undergraduate from the University of California at Berkeley) on a Department of Energy Summer Undergraduate Laboratory Internship to perform research using various instrumentation and facilities at Brookhaven National Laboratory and at Stony Brook. The PI also organized a tour for first-year Chemistry graduate students in which they visited a range of facilities, including the NSLS beam lines, the Positron Emission Tomography Facility, a host of spectroscopy and magnetic resonance imaging labs in the Chemistry Department, and an AFM lab in the Materials Science Department, many of which they ended up utilizing during their subsequent research. Faculty Organizer: Chemistry Research Day (November 4, 2005) – a day-long celebration of research achievements of departmental graduate students, undergraduates, high school students, and postdoctoral fellows associated with research at Stony Brook and BNL. A special emphasis was placed on inviting high school teachers and community college teachers (e.g. Suffolk Community College) and associated students as well as from participants from sister institutions (e.g. Hofstra University) to attend this event. CAREER: Rational Synthesis and Studies of Functionalized Carbon Nanotubes Stanislaus S. Wong, SUNY at Stony Brook, DMR