Engineering Nanomaterials and Interfaces in Energy Conversion and Storage
Guozhong Cao
University of Washington, Department of Materials Science and Engineering
Seattle, WA 98195-2120, gzcao@u.washington.edu
Nanostructured materials possess unique physical properties that are not found in their bulk counterparts, and some properties can be tailored by change the characteristic dimension of the nanomaterials. Devices and systems based on appropriately designed and fabricated nanostructures and nanomaterials can demonstrate remarkably enhanced performances. The large specific surface area and short diffusion distance can surely enhance the interface and transport kinetics, while the surface energy and defects will impact the phase transition and reaction thermodynamics. However, it is often overlooked that nanostructured materials can also introduce detrimental impacts on physical properties and device performances. In this presentation, I will use three examples to illustrate how energy conversion and storage efficiency can be significantly improved through careful design and engineering of materials on the nanometer and micrometer scales and through surface chemistry modification. The first example is hierarchically structured photoanodes for dye-sensitized solar cells and quantum dot sensitized solar cells, in which the controlled micro-sized aggregation of nanocrystallites resulted in light scattering within photoelectrodes. While a simple size reduction of nanocrystals may not lead to higher power conversion efficiency. The second example is nanostructured electrodes for lithium-ion batteries. Nanostructured electrodes have demonstrated specific energy and specific power improvements with excellent cyclic stability. Further enhancement in energy density can be achieved through introduction of defects and modification of surface chemistry. The third example is the manipulation and control of nanostructures and surface chemistry of porous carbon for supercapacitors.
曹国忠,美国华盛顿大学材料科学与工程系波音-施泰纳讲席教授、化学工程系教授、和机械工程系兼 职教授。又兼中国科学院北京纳米能源与纳米系统研究所研究员和大连理工大学教授。华东理工大学学士，中国科学院上海硅酸盐研究所硕士，荷兰爱因霍芬科技大学博士。目前的研究集中在纳米材料在能源领域的应用，涉及太阳能电池、离子电池、和超级电容器等方面。发表学术论文380余篇，外文论著7部，负责编撰会议论文集4本。
时间：2013年3月19日
地点：中国科学院化学研究所5号楼402会议室
