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Famu-Fsu College Of Engineering
Mei Zhang and Jian Li, “Carbon Nanotube in Different Shapes”, Materials Today 12, 12-18 (2009). (Invited review paper)
Ali E. Aliev, Jiyoung Oh, Mikhail E. Kozlov, Alexander A. Kuznetsov, Shaoli Fang, Alexandre F. Fonseca, Raquel Ovalle, Márcio D. Lima, Mohammad H. Haque, Yuri N. Gartstein, Mei Zhang, Anvar A. Zakhidov, Ray H. Baughman, “Giant-Stroke, Superelastic Carbon Nanotube Aerogel Muscles”, Science 323, 1575-1579 (2009).
Alexander A. Zakhidov, Dong-Seok Suh, Alexander A. Kuznetsov, Joseph N. Barisci, Edgar Muñoz, Alan B. Dalton, Steve Collins, Von H. Ebron, Mei Zhang, John P. Ferraris, and Anvar A. Zakhidov, Ray H. Baughman, “Electrochemically Tuned Properties for Electrolyte-Free Carbon Nanotube Sheets”, Advanced Functional Materials, 19, 2266–2272 (2009).
Tissaphern Mirfakhrai,a, Jiyoung Oh, Mikhail Kozlov, Shaoli Fang, Mei Zhang, Ray H. Baughman, and John D. W. Madden, “Carbon Nanotube Yarn Actuators: An Electrochemical Impedance Model”, Journal of the Electrochemical Society, 156, K97-K103 (2009).
Yiwen Chen, H. Y. Miao, Mei Zhang, Richard Liang, Chuck Zhang, and Ben Wang, “Optimizing the laser post-treatment parameters for carbon nanotube buckypaper field emission cold cathode via design of experiments”, Nanotechnology, 20, 325302 (2009).
V.R. Coluci, L.J. Hall, M.E. Kozlov, M. Zhang, S.O. Dantas, D.S. Galvão, and R.H. Baughman, “Modeling the auxetic transition for carbon nanotube sheets”, Physical Review B 78, 115408 (2008). (This paper has been selected by the editors of PRB to be an Editors' Suggestion)
Lee J. Hall1, Vitor R. Coluci, Douglas S. Galvão, Mikhail E. Kozlov, Mei Zhang, Sócrates O. Dantas, and Ray H. Baughman, “Sign Change of Poisson’s Ratio for Carbon Nanotube Sheets”, Science 320, 504-507 (2008).
Christopher D. Williams, Raquel Ovalle Robles, Mei Zhang, Sergey Li, Ray H. Baughman, Anvar A. Zakhidov, “Multiwalled carbon nanotube sheets as transparent electrodes in high brightness organic light-emitting diodes”, Applied Physics Letters 93, 183506 (2008).
Tissaphern Mirfakhrai, Jiyoung Oh, Mikhail Kozlov, Shaoli Fang, Mei Zhang, Ray H. Baughman, and John D. Madden, “Carbon Nanotube Yarns as High Load Actuators and Sensors,” Advances in Science and Technology, 61, 65-74 (2008).
Mei Zhang, Shaoli Fang, Anvar A. Zakhidov, Sergey B. Lee, Ali E. Aliev, Christopher D. Williams, Ken R. Atkinson, and Ray H. Baughman, “Strong, Transparent, Multifunctional Carbon Nanotube Sheets”, Science 309, 1215-1219 (2005).
Mei Zhang, Ken R. Atkinson, and Ray H. Baughman, “Multifunctional Carbon Nanotube Yarns by Downsizing an Ancient Technology”, Science 306, 1358-1361 (2004).
This invention is for fabricating freestanding graphene nanoribbons (GNRs) and GNR networks by unzipping carbon nanotubes (CNTs) in a freestanding CNT film using laser irradiation. It provides a novel solid-state process to fabricate freestanding GNRs and GNR networks.
Since CNTs are cylindrical shells made, in concept, by rolling graphene sheets into a seamless cylinder, the unzipping of CNTs is a new and very promising approach for controlled and large-scale GNR production. In this process, CNTs are unzipped (opened or fractured) along their longitudinal axes in such a way that the obtained structures are the desired GNRs. Another advantage of using CNTs as starting materials to produce GNRs resides in the fact that the vast existing knowledge on CNT synthesis and purification methods can be used to control and to optimize GNR fabrication.
Unzipping CNTs has been practiced in many different ways. However, these chemical and physical methods use strong acids, oxidizing agents, or other solvents. The wet-processes alter the properties of GNRs because of a high proportion of oxygen functionalities or particles and cause problems in device fabrication process because of wrinkles and folding of GNRs as well as positioning issues.
Our invention uses freestanding CNT sheets as the starting material and uses controlled laser irradiation in a preferred environment to convert (unzip) CNTs to GNRs and weld (joint) GNRs together to form GNR network. This is a solid-state fabrication process, which does not use any acids or solvents. Only this process is capable of fabricating large, freestanding GNRs and GNR networks and creating controllable CNT-graphene intramolecular junctions. Freestanding GNR networks are transparent conductive layers, which can be transferred easily onto any kind of substrates as a transparent electrode for various electronic and photonic applications. This solid state process is fast, clean, and scalable, and can be developed to a large-scale nanomanufacturing process.
Thermoelectric technology has been treated as a candidate to convert heat into electricity to reuse the waste heat. By using body heat, thermoelectric generators are promising when applied to wearable devices as the power source. Organic thermoelectric materials have drawn more and more attention in such applications due to their good flexibility, low density, low toxicity, low cost, low thermal conductivity, and good processability. In contrast to conductive polymers, the thermoelectric performance of insulating polymers, with better processability and lower cost, is limited by the low electrical conductivity. In this patent, polymer pyrolysis, which was reported to improve the electrical conductivity of some insulting polymers, was used to improve the thermoelectric properties of insulting polymer composites. The studies show that the structure conjugation during pyrolysis is beneficial to both the Seebeck coefficient and electric conductivity of polymer composites. The partially conjugated polymer composite obtained a comparable power factor to that of the conductive polymer composites. With the contribution of this method, more options are provided for the studies of flexible thermoelectric materials with better processability and lower cost.
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