Winnie Wong-Ng

Research Interests

• Materials for energy applications
• Thermoelectric standards, metrology, data, and materials
• Crystallography, phase equilibria, and crystal chemistry of functional materials
• Sorbent materials for sustainability applications
• Measurements and standards for batery and supercapacitor materials

 
Figure 1(left): Sustainability - planet earth; Figure 2(center): Combinatorial determination of the thermoelectric power factor as a function of composition for La- and Sr-doped Ca3Co4O9; Figure 3 (right): Crystal Structure of the low temperature Seebeck coefficient standard (Bi2Te3)

Postdoctoral Research Opportunities

Currently, a major challenge for the US economy is to provide inexpensive, efficient, compact, safe, and environmentally-friendly technologies for energy generation and conversion. Thermoelectric materials enable the direct conversion between thermal and electrical energy through the Seebeck and Peltier effects. Thermoelectric materials are currently undergoing a renaissance and are poised for large-scale applications. Recent improvements in thermoelectric conversion efficiency have made these materials attractive to the automotive industry for waste heat recovery applications, as well as in the environmental arena for reliable solid-state refrigeration, since no moving parts are involved. The properties of interest in thermoelectric materials include Seebeck coefficient, electrical resistivity, and thermal conductivity. This project addresses innovations required to measure those properties, as well as the establishment of standards for thermoelectric materials. The thermoelectric materials may be quantum dots, thin films, superlattice films, single crystals, or bulk metals, alloys or oxides. For more information... (50.85.21.B6767)

Knowledge of phase relationships and the structure of phases is essential for understanding and for developing structure-property relationships of functional materials (for example, materials for energy applications) and for optimizing processing strategies. The technical approach includes synthesis and characterization using x-ray and other diffraction methods. A wide range of collaborations for property measurements will be available throughout the NIST laboratories. For more information... (50.85.21.B4090)

Global warming is at least partially attributable to increased levels of CO2 in the atmosphere. The increased levels are of anthropogenic origin, mostly from coal-fired electrical power generation plants. Capture of the CO2 as it is emitted from the flue is one viable scheme to address this enormous environmental problem. The goal of this project is the highly efficient and inexpensive capture of CO2 using solid sorbent materials such as zeolites and metal-organic-framework (MOF) materials. Crucial factors for understanding the absorption efficiency of these materials are their chemical and physical reactivity with CO2, and their pore structure. The experimental work in this project will include the use of neutron and synchrotron beamline techniques such as neutron diffraction, synchrotron X-ray absorption spectroscopy, and small angle X-ray and neutron scattering. Such techniques will enable in-situ, real-time measurements of the structure of sorbents, pore interconnectivity, pore structure, CO2 distribution, and local absorbate/CO2 bonding structure. Further, X-ray diffraction analysis will be carried out in-situ with samples that are simultaneously undergoing evolved gas analysis and thermogravimetric analysis (TGA). The project will also address current needs for standards in the area of solid sorbents for CO2 capture.

Awards and Honors

• ICDD Board of Directors, member at large, 2010-2014
• US Department of Commerce Bronze Medal Award, 2008
• Richard & Patricia Spriggs Phase Equilibria Award, American Ceramic Society (ACerS), 2007
• Recognitions from ACerS for serving as Chair of the Electronics Division, 2005-2006
• Howard McMurdie Award, International Centre for Diffraction Data (ICDD), 2004
• US Department of Commerce Bronze Medal Award, 2002
• Fellow of ACerS, 2002
• PDF-4 Consulting Editor Award, ICDD, 2002
• Fellow of ICDD, 2000
• Recognitions from MRS as symposia organizer (2005, 1999) & short course organizer (1992)
• Recognitions from ACerS as symposia organizer (1998, 1999, 2001-2007)
• Recognitions from US Department of Energy (DOE) for receiving the highest scores in DOE Superconductivity Program Peer Reviews, 1997, 1999, and 2001 (plaques or certificates)
• Recognitions from the Association of NIST Asian Pacific Americans for serving as President, 2000-2003
• ICDD citations for distinguished contributions to the Powder Diffraction File (1996,1998-2006).
• Phi Kappa Phi, Phi Lambda Upsilon, Iota Sigma Pi, Sigma Xi