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报告题目 |
Nanomaterials in One Dimension: Exploring Mesoscopic Phenomena with Template-Grown Nanowires |
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报告时间 |
2014年9月23日下午15 : 30 |
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报告地点 |
合肥微尺度物质科学国家实验室一楼科技展厅 |
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报告人 |
Prof. Thomas E. Mallouk, The Pennsylvania State University |
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报告摘要 |
Mesoscopic properties emerge when the size of an object matches a characteristic physical length scale, such as the exciton radius in a semiconductor or the coherence length of Cooper pairs in a superconductor. Nanowires are particularly interesting in this context as quasi-1D materials. By using anodic alumina and track-etched polymer membranes as templates, we have made “striped” and core-shell nanowires with precise control over dimensions and composition. These structural features allow one to explore the unusual electronic transport properties of single-crystal nanowires. The motion of nano- and microwires in fluids is also a mesoscopic phenomenon because a crossover to new behavior occurs at low Reynolds number. Bi- and trimetallic nanorods are catalytically self-propelled in fuel-containing solutions at speeds that are comparable to those of flagellar bacteria. Despite the difference in propulsion mechanisms, catalytic nano- and micromotors are subject to the same external forces as natural motors such as bacteria. Therefore they follow the same scaling laws and exhibit similar emergent behavior (e.g., magnetotaxis, chemotaxis, schooling, and predator-prey behavior). Recently we have found that bimetallic nanowires also undergo autonomous motion and a range of collective behavior in fluids when excited by low power ultrasound. The acoustic propulsion mechanism may be particularly useful for biomedical applications because it is salt-tolerant and does not involve toxic chemical fuels. |
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报告人简介： Prof. Thomas E. Mallouk is Evan Pugh Professor of Materials Chemistry and Physics at the Pennnsylvania State University. His research focuses on the synthesis of inorganic materials and their application to solar energy conversion, catalysis and electrocatalysis, nano- and microscale motors, low dimensional physical phenomena, and environmental remediation. He is the author of approximately 350 publications published in Nature Chem., PNAS, JACS etc. (Citations: 24,700; h-index: 89). He is an Associate Editor of the Journal of the American Chemical Society and Associate Director of the Penn State MRSEC, the Center for Nanoscale Science. | |
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参加者：所有感兴趣的老师和学生 | |
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主办单位：化学与材料科学学院、微尺度、国际合作与交流部 | |