Department of Geology and Geophysics
1000 E. University Ave.
Laramie, WY 82071-2000
Low temperature and environmental geochemistry, mineral-water interface chemistry, photoelectrochemistry, geomicrobiology
Head's Office Phone 307-223-1027
Research Office Phone: 307-223-2312
Fax Phone: (307) 766-6679
Laramie, Wyoming 82071
Head's Office Room No: GE 124
Research Office Room No: ESB 3020
Lab Room No: ESB 3007/3009
Geology, PhD, Stanford University, 1991
Geology, BA, Dartmouth College, 1983
2014-2017: Development of Next Generation Hydrothermal Atomic Force Microscopy. National Science Foundation
2016-2017: Rachel Carson Center for Environment and Society, Interdisciplinary Fellowship, Ludwig Maximilian’s Universitaet, Munich, Germany (with Sarah Strauss, Anthropology)
2016-2019: Perchlorate production via photoelectrochemistry with semiconducting minerals on Mars: Processes and implications. NASA (with Bruce Parkinson, Chemistry)
Braun A., Hu Y., Boudoire F., Bora D.K., Sarma D.D., Graetzel M., Eggleston C.M. (2016) The electronic, chemical and electrocatalytic processes and intermediates on iron oxide surfaces during photoelectrochemicalwater splitting. Catalysis Today 260, 72-81.
Eggleston C.M. (2015) Renewable Energy on Campus at the University of Wyoming. In “Implementing Campus Greening Initiatives”, W. Leal Filho et al. (eds.), World Sustainability Series, Springer International Publishing, Switzerland.
Eggleston C.M., Strauss S. (2013) Energy transitions in south India and beyond. United States India Educational Foundation (USIEF, http://www.usief.org.in/alumni-news/Carrick-Eggleston.html
Xu J., Sahai N., Eggleston C.M., Schoonen M.A.A. (2013) Reactive oxygen species at the oxide/water interface: Formation mechanisms and implications for prebiotic chemistry and the origin of life. Earth and Planetary Science Letters 363, 156-167.
Yu H., Eggleston C.M., Chen J., Wang W., Dai Q., Tang J. (2012) Optical waveguide lightmode spectroscopy (OWLS) as a sensor for thin film and quantum dot corrosion. Sensors 12, 17330-17342, doi: 10.3390/s121217330
Eggleston C.M. (2012) Nature’s Nanostructures (book review), Elements Magazine, v. 8 issue 3, page 237.
Schuttlefield J.D., Sambur J.B., Gelwicks M., Eggleston C.M., Parkinson B.A. (2011) Photooxidation of chloride by oxide minerals: Implications for perchlorate on Mars. J. Am. Chem. Soc. Comm. 133, 17521-17523.
Meitl L., Eggleston C.M., Khare N., Colberg P.J.S., Reardon C.L., Shi L., Frederickson J.K., Zachara J.M. (2009) Electrochemical behavior of Shewanella oneidensis MR-1 and its outer membrane cytochromes: OmcA and MtrC impart redox activity with iron oxide electrodes. Geochimica et Cosmochimica Acta.
Eggleston C.M. (2008) Toward new uses for hematite. Science (Perspectives), 184-185.
Eggleston C.M., Voeroes, J., Shi, L., Lower B.H., Droubay T.C., Colberg, P.J.S. (2008) Binding and direct electrochemistry of OmcA, an outer-membrane cytochrome from iron reducing bacteria, with oxide electrodes: A candidate microbial fuel cell system. Inorganica Chimica Acta 361, 769-777.
Khare N., Eggleston C.M., Lovelace D.M., Boese S.W. (2006) Structural and redox properties of mitochondrial cytochrome c co-sorbed with phosphate on hematite (a-Fe2O3) surfaces. Journal of Colloid and Interface Science 303, 404-414.
Khare N., Lovelace D.M., Eggleston C.M., Swenson M., Magnuson T.S. (2006) Redox-linked conformation c hange and electron transfer between monheme c-type cytochromes and oxides. Geochimica et Cosmochimica Acta 70, 4332-4342.
Eggleston C.M., Khare N., Lovelace D. (2006) Cytochrome c interaction with hematite (a-Fe2O3) surfaces. Journal of Electron Spectroscopy and Related Phenomena 150 220-227.
Khare N., Eggleston C.M., Lovelace D.M. (2005) Sorption of mitochondrial cytochrome c to hematite surfaces: Implications for electron transfer. Clays and Clay Minerals 53, 564-571.
Rocks and minerals interact with their surroundings – our environment - via the chemistry that happens at their surfaces. Understanding the surface chemistry of minerals is key to understanding how geologic materials interact with, modulate, and control our environment. Mineral surfaces affect the composition of natural waters by partitioning solutes between solid and solution, catalysis, electron transfer (abiotic and otherwise), and simply by dissolving and growing.
Our research group has recently focused on photoelectrochemistry in both natural and engineered systems. We have shown, for example, that recent observations of abundant perchlorate on Mars can be explained through the action of sunlight on semiconducting minerals on Mars’ surface. The same basic chemistry is also involved in the loss of water from Mars, and most likely also had a profound effect on Earth’s oxygen history. We have recently been funded by NASA to study these processes under Mars-like conditions in a constructed “Mars Simulation Chamber”.
We have also been studying the photoelectrochemical properties of desert varnish, a rock coating often seen in deserts but which also occurs in other environments. This coating is often rich in manganese oxides, giving rise to its black color. In addition, the coating is also often rich in iron oxides, clay minerals, and bacteria known to have the ability to oxidize manganese and other metals. This has led to the idea that desert varnish is a biogenic rock coating. Our viewpoint is a bit different – while the desert varnish may be initiated by bacterial oxidation, the extremely slow growth of the varnish over tens of thousands of years indicates that the supply of energy to the system is too low to maintain bacterial metabolism. Our work indicates instead that the semiconducting oxides in the varnish absorb sunlight, oxidize a variety of materials from water to chloride to organic molecules, and produce reduced metals (Mn2+ and Fe2+) that can then be utilized by bacteria as an energy source.
I currently teach Geochemistry of Natural Waters (GEOL 4777/5777) and Geochemical Cycles and the Earth System (GEOL/ESSE 2000) in the fall semester, and either GEOL 1070 (an introductory Earth Science course specifically tailored for elementary education majors) or a course on the chemistry of surfaces and interfaces (GEOL 5420).
GEOL 1070 - The Earth: Its Physical Environment
GEOL/ESSE 2000 - Geochemical Cycles and the Earth System
GEOL 4777/5777 – Geochemistry of Natural Waters
GEOL 5420 – Surfaces and Interfaces