David O. Wipf

Henry Family Dean's Distinguished Professor of Chemistry

	David Wipf received his B.S. degree from the University of South Dakota in 1984 and in 1989 was awarded a Ph.D. in Analytical Chemistry from Indiana University, Bloomington. He was a Postdoctoral Fellow at the University of Texas at Austin before joining the Faculty of Mississippi State University in 1992.
	email:
	telephone: (662) 325-7608

Research Interests

Our research effort is focused on electroanalytical chemistry. A major topic of this research is in the use and development of the scanning electrochemical microscope (SECM) for microscopic examination of the electrochemical and chemical activity of surfaces immersed in electrolyte solutions. The SECM uses a micrometer-sized electrode probe to scan across the surface. An important capability of the SECM is its ability to image and modify the surfaces of insulating and conducting materials. We are using the SECM to explore the electrochemical properties of carbon electrodes by using the reaction-rate imaging ability to detect and measure rates of electron-transfer at microscopic regions of the carbon surface. The SECM can locally modify the surface of carbon by producing small regions of oxidized carbon or by generating functional groups that provide a base to attach enzyme molecules. SECM imaging is used to detect the activity of enzyme modified electrodes.

We are using the SECM for the study of composite materials and processes involved in corrosion. We are especially interested in the processes involved in passive-layer breakdown and mechanisms for the initiation and formation of localized corrosion. By using the SECM to both initiate and examine, in real time, localized corrosion sites we hope to rationally investigate the mechanism for corrosion formation and propagation.

We are also interested in the use of SECM to etch or deposit bulk materials in localized regions. The image shows the deposition of a microscopic pattern of conducting polymer with the SECM.

Publications 2003 - 2008

1. "An In-situ Electrochemical STM Study of Potential-Induced Coarsening and Corrosion of Platinum Nano Crystals," Qingmin Xu, Eric Kreidler, David Wipf, and Ting He, J. Electrochem. Soc., In press.
2. "Feedback Effects in Combined Fast-Scan Cyclic Voltammetry-Scanning Electrochemical Microscopy," Daniel S. Schrock, David O. Wipf, and John E. Baur, Anal. Chem.,2007, 79, 4931-4941.
3. "Microparticle-Based Iridium Oxide Ultramicroelectrodes for pH Sensing and Imaging," Emad El-Deen M. El-Giar and David O. Wipf, J. Electroanal. Chem., 2007, 609, 147-154.
4. "In Situ Electrochemical STM Study of the Coarsening of Platinum Islands at Double-Layer Potentials," Qingmin Xu, Ting He, and David O. Wipf, Langmuir, 2007, 23,9098- 9103.
5. "Fast-Scan Cyclic Voltammetry - Scanning Electrochemical Microscopy," Luis Díaz-Ballote, Mario Alpuche-Aviles, and David O. Wipf, J. Electroanal. Chem., 2007, 604, 17-25.
6. "An Electrochemical STM Study of Coarsening and Corrosion of Platinum Films," Qingmin Xu, Eric Kreidler, David Wipf, and Ting He, ECS Trans., 2007, 11(1), 1279-1287.
7. "Simple Fabrication of a Silver Epoxy Coated Microelectrode for SECM Imaging in Small Volumes," Luis Díaz-Ballote and David O. Wipf, ECS Trans., 2007, 3(31), 249-258.
8. "Preparation of Tip-Protected Poly(oxyphenylene) Coated Carbon-Fiber Ultramicroelectrodes," Emad El-Deen M. El-Giar and David O. Wipf, Electroanalysis, 2006, 18, 2281-2289.
9. "Review of laboratory and outdoor exposure efficacy results of organic biocide: Antioxidant combinations, an initial economic analysis and discussion of a proposed mechanism," Tor P. Schultz, Darrel D. Nicholas, William P. Henry, Charles U. Pittman, David O. Wipf and Barry Goodell, Wood Fiber Sci., 2005,37, 175-184.
10. "Scanning Electrochemical Micrscopy of Model Neurons: Constant Distance Imaging," Ruwan T. Kurulugama, David O. Wipf, Sara. A. Takacs, Sirinun Pongmayteegul, Paul A. Garris, and John E. Baur, Anal. Chem., 2005, 77, 1111 -1117.
11. "Voltammetry and Surface Analysis of AISI 316 Stainless Steel in Chloride-Containing Simulated Concrete Pore Environment," Lucien Veleva, Mario Alpuche-Aviles, and David O. Wipf, J. Electroanal. Chem, 2005, 578, 45-53.
12. "Activity of SiC Particles in Al-Based Metal Matrix Composites Revealed by SECM," L. Diaz-Ballote, David O. Wipf, L. Veleva, M. A. Pech-Canul, M. I. Pech-Canul, J. Electrochem. Soc., 2004, 151, B299-B303.
13. "Scanning Electrochemical Microscopy of Model Neurons: Imaging and Real-Time Detection of Morphological Changes," Johanna M. Liebetrau, Heather M. Miller, John E. Baur, Sara A.Takacs, Rick Crous, Vipave Anupunpisit, Paul A. Garris, David O. Wipf, Analytical Chemistry, 2003, 75, 563-571.
14. "Patterning and Imaging of Oxides on Glassy Carbon Electrode Surfaces by Scanning Electrochemical Microscopy," Robert C. Tenent and David O. Wipf, J. Electrochem. Soc., 2003, 150, E131-E139.
15. "An in situ Electrochemical Study of Electrodeposited Nickel and Nickel-Yttrium Oxide Composite Using Scanning Electrochemical Microscopy," L. Veleva, L. Diaz-Ballote and David O. Wipf, J. Electrochem. Soc., 2003, 150, C1-C6.

Book Chapters

1. "Analytical and Digital Instrumentation," David O. Wipf in The Encyclopedia of Electrochemistry, Vol 3: Instrumentation and Electroanalytical Chemistry, A. J. Bard, M. Stratmann, and G. S. Wilson, Eds, Vch Verlagsgesellschaft Mbh, Weinheim, 2003.
2. "Scanning Electrochemical Microscopy," David O. Wipf in The Encyclopedia of Imaging Science and Technology, J. P. Hornak, Ed, John Wiley & Sons, Inc., New York, 2002, pp 1248-1259.