ChE Tulsa University

 
           

Dr. Laura P. Ford

Associate Professor of Chemical Engineering

Email: laura-ford@utulsa.edu 

Research Emphasis

  • Surface science - UHV
  • Kinetics of etching metals with ß-diketones
  • Surface chemistry of etching metals with ß-diketones
Research
Surface science – UHV

Getting to a pressure this low is not easy.  In the center right of the picture you can see a window surrounded by a circle of bolt heads.  Everything attached to the chamber must have a seal that uses metal gaskets.  Gaskets made from rubber or other polymers outgas too much, and the chamber pressure would never get down to UHV range!  The white bands wrapped around the chamber are heater tapes.  The water adsorbed on the inside walls of the chamber also keeps us from getting to UHV, so we have to "bake" the chamber by heating it.  The heating makes the water leave the walls, much like the condensate on the outside of your cold soda can evaporate as the soda can warms up. 

This chamber has three different kinds of analytical equipment.  The piece sticking out on the center left is the Auger electron spectrometer.  The spectrometer shoots a beam of electrons at our solid surface.  The electrons in the solid become excited and then relax.  As they relax, some electrons are emitted from the solid itself.  The spectrometer collects these emitted electrons and determines what element emitted them based upon their energies.  We use this technique to check the cleanliness of our solids. 

The other pieces of analytical equipment are the mass spectrometer and the infrared spectrometer, but you can't see them in the picture.  The mass spectrometer ionizes the gases in the chamber.  The gases usually fragment when they are ionized.  The spectrometer collects the ionized fragments and then determines the mass to charge ratio of each ionized fragment.  From these mass to charge ratios, we can determine what the original gas phase molecule was.  We use mass spectrometry to determine what the products of reactions occurring on the surface are.  The infrared spectrometer shoots an infrared beam at the solid.  The molecules on the surface vibrate in response to the infrared beam, and the reflected infrared beam that leaves the solid is different from the original beam because of these interactions.  By comparing the original and reflected beams, we can decide what molecules are on the surface and how the different atoms are connected. 

The surface science chamber is used in studying the surface chemistry of etching metals with ß-diketones (see below). 

 

Kinetics of etching metals with ß-diketones

ß-diketones, such as 1,1,1,5,5,5-hexafluoro-2,4-pentanedione, can be used to etch oxidized metal surfaces. This has potential applications in metals removal in the microelectronics industry and in particle redispersion in catalysts. The kinetics of this etching reaction will be studied under low vacuum conditions in a glass flow reactor. The effects of oxidant, ß-diketone, relative proportions of oxidant and ß-diketone, temperature, total pressure, and surface treatment will be studied on both metals and metal alloys.  Right now we are studying the fine-tuning of the copper content in copper indium diselenide, which is a photovoltaic material.  

Surface chemistry of etching metals with ß-diketones

The surface chemistry of ß-diketone metal etching will be studied under ultra-high vacuum conditions. Ultra-high vacuum conditions allow us to control the environment of the metal and to look carefully at the reactants and their formation temperatures. The effects of surface, oxidant, ß-diketone, relative proportions of oxidant and ß-diketone, and temperature can also be studied in ultra-high vacuum. Right now we are looking at copper and nickel-iron alloys. This work is supported by the National Science Foundation grant # DMR-0405394.

Selected Publications  

  • Christi L. Patton and Laura P. Ford, "Chemically Powered Toy Cars:  A Way to Interest High School Students in a Chemical Engineering Career",  Proceedings of the 2003 American Society for Engineering Education Annual Conference and Exposition, June 22-25, 2003, Nashville, TN.
  • L. P. Ford, "Water Day:  An Experiential Lecture for Fluid Mechanics", Chemical Engineering Education 37 (2003) 170 - 173.
  • Aditya Moralwar, Kerry L. Sublette, Laura P. Ford, Kathleen Duncan, Greg Thoma, and Josh Brokaw, "Remediation of a Spill of Crude Oil and Brine Without Gypsum", Environmental Geosciences 12 (2005) 115 - 125.
  • Laura P. Ford and Christi L. Patton, "Attracting High School Students to Engineering by Adapting a National Collegiate Competition", Proceedings of the 2004 American Society of Engineering Education Midwest Section Conference, September 29 – October 1, 2004, Pittsburg, KS, http://www.pittstate.edu/asee/aseemwmeeting/papers.html, posted Sept. 3, 2004.
  • Chintan Mehta, Aditya Moralwar, Kerry Sublette, Laura Ford, Kathleen Duncan, Joshua Brokaw, Tim Todd, and Greg Thoma, "Soil Ecosystem Recovery Following Managed and Unmanaged Bioremediation of a Terrestrial Crude Oil Spill", Proceedings of the XIVth International Colloquium on Soil Zoology and Ecology, August 30 – September 3, 2004, Université de Rouen, Mont Saint Aignan, France. 
  • Christi L. Patton, Laura P. Ford, and Daniel W. Crunkleton, "Welcome to ChE:  Chocolate Engineering", Proceedings of the 2005 Annual Meeting of the American Institute of Chemical Engineers, Oct. 30 – Nov. 4, 2005, Cincinnati, OH.
  • Laura P. Ford and Christi L. Patton, "A Chemical Engineering Competition for Middle and High School Students", Proceedings of the 2005 Annual Meeting of the American Institute of Chemical Engineers, Oct. 30 – Nov. 4, 2005, Cincinnati, OH.

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