Research Interests:
"Life at the edge"-Surfaces are where the action is.
Our research program is aimed at characterizing and understanding chemical reactions at surfaces. Interfacial processes and surface chemistry are at the heart of technologies associated with the chemical and petroleum industries, functioning of batteries and fuel cells, production of microelectronic devices, and design and fabrication of sensors and diagnostic devices, and play key roles in heterogeneous processes in environmental and atmospheric chemistry. By discovering novel methods to alter and control surface chemistry we seek to develop new catalysts for specialty chemical synthesis, make advanced materials with novel properties, and build functional nanostructures from a "bottom-up" approach utilizing directed manipulation and layered nanofabrication at surfaces and interfaces. Surfaces are central to nanoscience and technology, modifying and controlling important properties of nanoparticles and electrical contacts. We employ a wide array of surface analytical techniques in our work, including scanning tunneling microscopy (STM), high-resolution X-ray photoelectron spectroscopy (HR-XPS), high-sensitivity low energy ion scattering (HS-LEIS), and infrared reflection-absorption spectroscopy (IRAS).
Research activities include: (i) understanding the structure, reactivity, and catalysis of bimetallic Pt alloys, (ii) characterizing oxidation and reduction reactions at core-shell zero-valent iron nanoparticles (nZVI) used for environmental remediation, (iii) characterization of novel PEM fuel cell electrodes, (iv) development of Rutherford backscattering (RBS) as a probe of liquid-solid interfaces, (v) probing chemistry and catalysis at Au surfaces and nanoparticles, (vi) elucidating kinetics and mechanism of ozonolysis of hydrocarbon films, (vii) investigating bond-selective chemistry using low energy electrons and ions, and (viii) measurements and fabrication of nanostructures by self-assembly and directed manipulation.
Teaching Interests:
I particularly enjoy teaching in the General (Freshman) Chemistry program. I show how applications of chemistry are everywhere and communicate the excitement of recent scientific advances, e.g. , observation, manipulation, and control of reactivity at the atomic scale. At the graduate level, I have primarily taught a course in Surface Chemistry. Depending on student interest, this course emphasizes various aspects of the field, such as kinetics, bonding, mechanistic chemistry, catalysis, deposition and growth, or surface analysis.
Recent Publications:
“Improving Electrocatalysts for O2 Reduction by Fine-tuning the Pt-support Interaction: Pt Monolayer on the Surfaces of a Pd3Fe(111) Single-Crystal Alloy”, W.-P. Zhou, X. Yang, M. Vukmirovic, B. E. Koel, J. Jiao, G. Peng, M. Mavrikakis, and R. Adzic, J. Amer. Chem. Soc., 131(35), 12755-12762 (2009).
“Simultaneous Oxidation and Reduction of Arsenic by Zero-Valent Iron Nanoparticles: Understanding the Significance of the Core-Shell Structure”, M. A. Ramos, W. Yan, X.-Q. Li, B. E. Koel, and W.-X. Zhang, J. Phys. Chem. C, 113(33), 14591-14594 (2009).
“STM and LEED observations of a c(2 x 2) Ge overlayer on Pt(100)”, T. Matsumoto, M. Batzill, and B. E. Koel, Surface Sci., 603(15), 2252-2262 (2009).
“Formation and Structure of a (?19x?19)R23.4?-Ge/Pt(111) Surface Alloy”, C.-S. Ho, S. Banerjee, M. Batzill, D. E. Beck, and B. E. Koel, Surface Sci., 603, 1161-1167 (2009).
“Investigation of CO oxidation transient kinetics on an oxygen pre covered Au(211) stepped surface”, J. Kim, E. Samano, and B. E. Koel, Catal. Lett., 128, 263-267 (2009).
“An IRAS study of CO bonding on Sn/Pt(111) surface alloys at maximal pressures of 10 Torr”, A. Hightower, M. D. Perez, and B. E. Koel”, Surface Sci., 603, 455-461 (2009).
“A Study of Iodine Adlayers on Polycrystalline Gold Electrodes by in-situ Electrochemical Rutherford Backscattering (ECRBS)”, A. Hightower, B. E. Koel, and T. Felter, Electrochimica Acta, 54, 1777-1783 (2009).
“Oxygen adsorption and oxidation reactions on Au(211) surfaces: Exposures using O2 at high pressures and ozone (O3) in UHV”, J. Kim, E. Samano, and B. E. Koel, Surface Sci., 600, 4622-4632 (2006).
“CO Adsorption and Reaction on Clean and Oxygen-Covered Au(211) Surfaces”, J. Kim, E. Samano and B. E. Koel, J. Phys. Chem. B, 110, 17512-17517 (2006).
Chapter 3.8.4 “Adsorbed CO2, NO2, O3, SO2, OCS, and N2O on Metals”, C. Panja, J. Kim, E. C. Samano, and B. E. Koel, in Adsorbed Layers on Surfaces, Landolt-Bornstein Volume III/42 , H. Bonzel (Ed.), (Springer-Verlag, Berlin-Heidelberg, 2006), pp. 170-241.
“Catalytic oxidation of HCN over a 0.5% Pt/Al2O3 catalyst”, H. Zhao , R. G. Tonkyn, S. E. Barlow, B. E. Koel, and C. H. F. Peden, Applied Catalysis B: Environmental, 65, 282-290 (2006).
“Fractional factorial study of HCN removal over a 0.5% Pt/Al2O3 catalyst: Effects of temperature, gas flow rate, and reactant partial pressure”, H. Zhao, R. G. Tonkyn, S. E. Barlow, C. H. F. Peden, and B. E. Koel, Ind. Eng. Chem. Res., 45, 934-939 (2006).
“Desorption of Chemisorbed Carbon on Mo(100) by Noble Gas Ion Sputtering: Validation of Ground Test Measurements of Ion Engine Lifetimes,” C.-S. Ho, S. Banerjee, B. E. Koel. O. B. Duchemin, and J. E. Polk, Appl. Surface Sci., 252, 2657-2664 (2006).
"Demonstration of an In-situ Electrochemical RBS System to Study Electrode-Electrolyte Interfaces", A. Hightower, B.E. Koel, and T. Felter, in Electrode Processes VII (from the 206th Meeting of The Electrochemical Society, Honolulu, HI, Oct. 3-8, 2004, ECS Proceedings, Vol. 2004-18) , V.I. Birss, D. Evans, M. Josowicz, and M. Osawa (Eds.), (ECS,Pendington, NJ, 2005), p. 46-54.
"Fabrication of Polystyrene Latex nanostructures by Nanomanipulation and Thermal Processing," E. Harel, S.E. Meltzer, A.A.G. Requicha, M.E. Thompson, and B.E. Koel, Nano Lett., 5, 2624-2629 (2005).
"TPD and FT-IRAS investigation of ethylene oxide (EtO) adsorption on a Au(211) stepped surface", J. Kim and B.E. Koel, Langmuir, 21, 3886-3891 (2005).
"Hydrogenation of 1,3-butadiene on two ordered Sn/Pt(111) surface alloys", H. Zhao and B.E. Koel, J. Catal., 234, 24-32 (2005).
"Reactivity of Ethyl Groups on a Sn/Pt(111) Surface Alloy", H. Zhao and B.E. Koel, Catal. Lett., 99, 27-32 (2005).
"Influence of coadsorbed hydrogen on ethylene adsorption and reaction a ( 3x 3)R30°-Sn/Pt(111) surface alloy", H. Zhao, and B.E. Koel, Langmuir, 21(3), 971-975 (2005).