纳米线储能材料与器件
麦立强教授（武汉理工大学）
时间：2013年5月17日10:00
地点：联合楼a座二楼会议室
麦立强，武汉理工大学材料学科首席教授，博士生导师，武汉理工大学-哈佛大学纳米联合重点实验室执行主任，国际刊物j nanosci lett副主编。2004年获武汉理工大学材料学专业博士学位， 2006-2007、2008-2011分别在美国佐治亚理工学院zl wang教授课题组从事博士后、高级研究学者研究。主要从事新能源纳米材料与器件研究，率先设计组装了单根纳米线全固态电化学储能器件，原位表征和揭示了纳米线电极容量衰减的内在规律，发表sci论文72篇；以第一或通讯作者发表nature commun、pnas、scientific reports、adv mater、nano lett、npg asia mater、mater today 14篇，被nature亚洲材料网站、德国nanowerk网站、美国权威替代能源网站等作专题报道。主持国家自然科学基金、国家重大基础研究计划课题、新世纪优秀人才支持计划等十余项项目；已授权国家发明专利16项。获全国优秀博士论文提名论文、全国大学生“挑战杯”特等奖指导教师、湖北省自然科学优秀学术论文特等奖等。
nanowire devices for electrochemical energy storage()
liqiang mai(麦立强)
state key laboratory of advanced technology for materials synthesis and processing, wut-harvard joint nano key laboratory, wuhan university of technology, wuhan 430070, china
e-mail: [email]mlq518@whut.edu.cn[/email]
nanomaterials have attracted increasing interest because they can offer a range of unique advantages in many energy related fields. for previous lithium battery application, bulk materials made of nanomaterials were usually used as the electrodes. although the electrochemical properties could be improved, the fast capacity fading is still one of the key issues and the intrinsic reasons are not clear until now. in situ probing has been increasingly employed in nanotechnology. to understand intrinsic reason of capacity fading, we designed the single nanowire electrochemical devices for in situ probing the direct relationship between electrical transport, structure, and electrochemical properties of the single nanowire electrode, which may push the fundamental limits of the nanowire materials for energy storage applications. in this device, single vanadium oxide nanowire or single si/a-si core/shell nanowire was used as working electrode, and electrical transport of the single nanowire was recorded in situ to detect the evolution of the nanowire during charging and discharging. our results show that conductivity of the nanowire electrode decreased during the electrochemical reaction, which limits the cycle life of the devices. based on this conclusion, we used prelithiation to restrain the conductivity decrease to improve the cycling performance of electrochemical devices. lb technique to assemble vo2 nanowires as thin film li-ion battery, which can decrease the boundary resistance and improve cycling property. we fabricated hierarchical mnmoo4/comoo4 heterostructured nanowires by combining "oriented attachment" and "self-assembly", which shows a high specific capacitance and good reversibility with a cycling efficiency of 98% after 1,000 cycles. to enhance stability of nanowire electrodes, we design and synthesized svo/pani triaxial nanowires by combining in situ chemical oxidative polymerization and interfacial redox reaction. it is expected that our study may extend effective and helpful methods in directions that will solve the challenge of property degradation in energy storage and open new applications.