Tag: Fall 2014

MSE Seminar: Disorder-Engineered Titanium Dioxide Nanocrystals: Fundamentals and Application to Solar-Driven Hydrogen Production

Materials Science & Engineering Department at Michigan Technological University; John & Virginia Towers Distinguished Lecture Series, Samuel S. Mao, University of California at Berkeley, Friday December 5, 2014
11:00 am – 12:00 pm, Room 610, M&M Building

Title: Disorder-Engineered Titanium Dioxide Nanocrystals: Fundamentals and Application to Solar-Driven Hydrogen Production;

This seminar will provide an overview of recent progress in the development of earth-abundant photocatalytic materials for solar-driven production of hydrogen. The emphasis will be the realization of disorder-engineered titanium dioxide, starting with an introduction of the fundamental concept behind disorder engineering. The method of synthesizing disorder-engineered titanium dioxide nanocrystals will be presented, followed by measurements of their structural, optical, and electronic properties. Photocatalysis experiments based on solar-driven hydrogen production using disorder-engineered titanium dioxide nanocrystals, that can absorb solar energy in both visible and infrared wavelength regions, will be summarized, and the physics underlying visible light absorption as well as an increased photocatalytic efficiency of disorder-engineered titanium dioxide nanocrystals will be discussed.

Speaker Bio: Professor Samuel Mao obtained his Ph.D. degree from the University of California at Berkeley in 2000. He is Director of Clean Energy Engineering Laboratory of the University of California at Berkeley. In 2013, he founded the Institute of New Energy, a private international research institution, after raising more than $15 million startup fund. He was also a career staff scientist at U.S. Department of Energy’s Lawrence Berkeley National Laboratory between 2001 and 2013. He published 130 refereed articles, which have received over twenty-thousand (20,000) citations. He is also an inventor of more than 20 patents, and has delivered 100 plenary, keynote, or invited talks at various international conferences and leading universities. He has served as a technical committee member, program review panelist, grant evaluator, and national laboratory observer for the U.S. Department of Energy. He co-founded the First International Symposium on Transparent Conducting Materials, the First International Conference on Energy Nanotechnology, and the First International Workshop on Renewable Energy. He co-chaired Materials Research Society (MRS) annual meeting in the spring of 2011, and the International Conference on Clean Energy in 2012. He received 2011 “R&D 100” Technology Award.

MSE Seminar: Properties of Glassy Polymers at the Nanoscale versus the Bulk State

Materials Science and Engineering Department, John & Virginia Towers Distinguished Lecture Series Seminar, Tuesday, October 7, 2014, 11:00 am – 12:00 pm, Room 610 M&M Building;

Donald R. Paul, University of Texas at Austin, Title: Properties of Glassy Polymers at the Nanoscale versus the Bulk State

The need for more energy efficient processes continues to drive interest in polymeric membranes for gas separations; removal of carbon dioxide and other impurities from natural gas is one of the important targets for this technology. There is interest in the discovery of new polymer structures for membranes that are more permeable, more selective or more robust particularly with regard to resisting plasticization by highly soluble gases like carbon dioxide. In general, the best polymers for these applications have high glass transition temperatures.

To achieve commercially attractive levels of flux or productivity, most membranes have an asymmetric or composite structure where the separating layer is very thin, of the order of 100 nm in thickness. It is generally assumed that these thin layers have the same permeation properties as thick films, tens of microns in thickness, which are easily prepared in the laboratory for evaluation of membrane materials. In fact, the usual method for estimating the thickness of the separating layer is to compare its gas permeance or flux to the permeability of a thick film. However, there is growing evidence that thin films of glassy polymers with thicknesses of a few hundred nanometers behave quite differently than thick films. A major factor is the observation that thin glassy films undergo physical aging, i.e., approach towards equilibrium, much more rapidly than do bulk glasses presumably due to high segmental mobility at free surfaces. This presentation will summarize recent evidence concerning the differences between thin and thick films with regard to aging, plasticization and thermal history based on gas permeation observations.

Dr. Donald R. Paul is the Ernest Cockrell, Sr. Chair professor in Department of Chemical Engineering at University of Texas at Austin. Prof. Paul got his bachelor degree from North Carolina State College and his master and Ph.D. degree from The University of Wisconsin at Madison. Professor Paul’s research interests include the broad areas of polymer science and engineering and chemical engineering with more than 700 papers published in prestigious journals. He obtained many awards and honors. He is an Elected Member of National Academy of Engineering (1988), Mexican Academy of Sciences (2001), and the Academy of Sciences of Bologna (2011). He is a Fellow for numerous important societies, including the Society of Plastics Engineers (2004), the American Chemical Society (2009), the Materials Research Society (2009), and the ACS Polymer Division (2011). He won Outstanding Lifetime Achievement Award (SPE-TPM&F) (2011), General Motors R&D Most Valued Colleague Award (2009), AIChE Founders Award (2008), Herman F. Mark Polymer Chemistry Award (American Chemical Society) (2005), Alan S. Michaels Award for Innovation in Membrane Science and Technology (NAMS) (2005); NAMS Founders Award (2005); American Chemical Society E.V. Murphree Award (1999); Council for Chemical Research Malcolm E. Pruitt Award (1999); AICHE William H. Walker Award (1998); Society of Plastics Engineers International Award (1993); Society of Plastics Engineers Education Award (1989); AIChE Materials Engineering and Sciences Division Award (1985); American Chemical Society Phillips Award for Applied Polymer Science (1984); Engineering News-Record Award (1976); and the American Chemical Society Arthur K. Doolittle Award (1973) etc. He was the Director of Texas Materials Institute (1998-2011) and the editor-in-chief of Industrial & Engineering Chemistry Research (an ACS journal).

DONALD PAUL PDF

MSE Seminar: Zhiqun Lin, Georgia Institute of Technology

John and Virginia Towers Distinguished Lecture Series, Materials Science and Engineering Graduate Seminar: Zhiqun Lin, Professor, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA; 11:00am-12:00 on Tuesday September 9th at M & M 610

Topic: A Robust Strategy to Monodisperse Functional Nanocrystals with Precisely Tunable Dimensions, Compositions and Architectures for Solar Energy Conversion and Photocatalysis

Nanocrystals exhibit a wide range of unique properties (e.g., electrical, optical, and optoelectronic) that depend sensitively on their size and shape, and are of both fundamental and practical interest. Breakthrough strategies that will facilitate the design and synthesis of a large diversity of nanocrystals with different properties and controllable size and shape in a simple and convenient manner are of key importance in revolutionarily advancing the use of nanocrystals for a myriad of applications in lightweight structural materials, optics, electronics, photonics, optoelctronics, magnetic technologies, sensory materials and devices, catalysis, drug delivery, biotechnology, and among other emerging fields. In this talk, I will elaborate a general and robust strategy for crafting a large variety of functional nanocrystals with precisely controlled dimensions (i.e., plain, core/shell, and hollow nanoparticles) for use in energy-related applications (i.e., solar cells and photocatalysis) by capitalizing on a new class of unimolecular star-like block copolymers as nanoreactors. This strategy is effective and able to produce organic solvent-soluble and water-soluble monodisperse nanoparticles, including metallic, ferroelectric, magnetic, luminescent, semiconductor, and their core/shell nanoparticles, which represent a few examples of the kind of nanoparticles that can be produced using this technique. The applications of these functional nanocrystals on plasmonic solar cells and photocatalysis will also be discussed.

Seminar on Sept 9 (Zhiqun Lin from Georgia Tech) PDF