报告时间：2013年7月29日（星期一）上午10:00-11:00

报告地点：能源基础楼一楼会议室

报告人：Dr. Li-Qiong Wang

Department of Chemistry, Brown University, Providence, US

报告摘要：

Structures and porosity including interconnectivity of micro- and nano-porosity play an important role in the performance of porous electrode materials. The information obtained on structural and porosity changes in electrode materials during a chargedischarge cycle provides insights to a better understanding of chemical and mechanical degradation mechanisms and a better design of electrodes. The pore geometry in most porous materials, even in the ordered mesoporous silica, is complex with interconnected cages, channels and micropores. It is challenging to directly characterize the interconnectivity of the pores in nano or meso-porous materials. The techniques such as small angle x-ray or neutron scattering and gas absorption do not provide direct information on how channels and cages are connected. In this presentation, we will demonstrate that hyperpolarized (HP) 129Xe NMR is a powerful and unique tool in probing porosity and interconnectivity in nanostructured materials. The porosity and interconnectivity of pores in highly crystalline mesoporous TiO2 with and without added graphene sheets (anode materials) have been investigated using HP 129Xe NMR. The HP 129Xe NMR results suggest that TiO2 and graphene are mixed uniformly on the nanoscale and the resulting hybrid nanostructure has better channel connectivity between different domains, enhancing the transport property for Liinsertion/ extraction. In addition, our ongoing work involves using HP 129Xe NMR in combination with other solid-state NMR techniques (such as 7Li and 29Si NMR) to study structural and porosity changes in electrode materials during a charge-discharge cycle.

报告人简介：

Education

B.S. in Chemistry, Wuhan University, China, GPA 4.0, August 1982

Ph.D. in Chemistry, University of California, Berkeley, CA, GPA 4.0, June 1993

Professional appointments

1991 – 1993 Research Chemist, Chevron Chemical Company

1993 – 2005 Senior Research Scientist, Material Science Department, Pacific Northwest National Laboratory

2003 – 2009 Adjunct Associate Professor, Materials Science Program, Washington State University

2005 – 2009 Chief Scientist, Division of Fundamental Science, Pacific Northwest National Laboratory

2009 – Present Lecturer/Research Prof., Department of Chemistry, Brown University

Awards and Recognitions

？R&D 100 Awards (1998).

？Discover Magazine Awards Finalist (1998).

？DOE Materials Science Award (1998).

？Pacific Northwest National Laboratory Environmental Health Science Division

Outstanding Performance Award (2000).

？Pacific Northwest National Laboratory Outstanding Team Performance Award (2000),

“Low K Mesoporous Dielectrics.”

？Pacific Northwest National Laboratory Outstanding Team Performance Award (2001),

“Development of a Commercially Viable NTP-Catalyst NOx Reduction Technology.”

？Pacific Northwest National Laboratory Energy Science and Technology Directorate

Outstanding Performance Award for Outstanding Research Progress Funded by the

Office of Basic Energy Sciences (2002).

？Pacific Northwest National Laboratory Energy Science and Technology Directorate

Outstanding Performance Award for “Design, Synthesis and Characterization of Solution

Templated Nanoarchitectured Materials” (2003).

？Exceptional Contribution Award (2003).

？Pacific Northwest National Laboratory Energy Science and Technology and Fundamental

Science Directorate Outstanding Performance Award for Outstanding Project Research-

DOE Basic Energy Sciences (2004).

？Pacific Northwest National Laboratory Energy Science and Technology and Fundamental

Science Directorate Outstanding Performance Award for “developing and implementing

129Xe NMR spectroscopy at PNNL (2008).

？Sheridan Teaching Fellow AY 2012-2013

Service to the Scientific and Engineering Community: Member of the American Chemical

Society, Materials Research Society, and American Vacuum Society.

报告联系人：502组 石瑛（9128）