Tyler Ewing

Scholar: Tyler Ewing

 Tyler Ewing

Major: Biochemistry & Molecular Biology

Faculty Mentors: Dr. Sergey Varganov 

Research Topic: Computational Study of Hydrogen Binding to the Rubredoxin Protein Model

Abstract: Platinum-based catalysts are currently used to accelerate a variety of chemical reactions, such as the formation and dissociation of molecular hydrogen. However, platinum is both expensive and will not satisfy the demand for catalysts as clean energy becomes more prevalent. Rubredoxin, a simple iron-sulfur protein essential for electron transport within living organisms, may have the potential of replacing these platinum-based catalysts with iron-based compounds at a reduced cost. The goal of this work is to determine which oxidation and multiplicity states of iron and nickel-substituted rubredoxins can bind and catalytically activate molecular hydrogen. Specifically, the high- and low-spin states of the Fe(II), Fe(III), Ni(I), and Ni(II) complexes are investigated. Calculations are also performed on each complex in the presence of molecular hydrogen to observe the effects hydrogen binding has on the structure and overall energy of the complex. The equilibrium geometry and potential binding energy of the rubredoxin and Ni-substituted active sites are determined using computational electronic structure methods. The fragment molecular orbital (FMO) method with density functional theory implemented in the GAMESS suite of programs is utilized. The FMO-DFT calculations are carried out using the def2-SV(P) basis set and PBE functional. Preliminary data shows hydrogen binding to all Fe complexes. However, the Ni-substituted rubredoxin model does not allow molecular hydrogen to bind as easily. With additional computations, this data will be useful for efforts in replacing platinum-based catalysts with inexpensive bio-inspired catalysts in the production of hydrogen fuel.

New Scholar: 2017 cohort