(4m) Nanostructured Materials for Solar Energy Conversion

Title: Nanostructured Materials for Solar Energy Conversion

Author: C.D. Bohn

The sun provides 10,000 times more energy to the earth than the current global consumption rate of 16 TW.  Storing solar energy to overcome diurnal supply is critical for meeting growing energy demand.  My future research lab will focus on solar energy technologies including (i) photoelectrochemical (PEC) hydrogen production, i.e. solar water splitting, and (ii) solar thermochemical cycles for fuel production. 

Inexpensive metal oxides such as α-Fe₂O₃ with a bandgap of approximately 2.1 eV can theoretically exceed a photoelectrochemical solar to hydrogen efficiency of 10 %. In my poster, I show that activating n-type dopants in iron oxide by thermal annealing improves efficiency by three orders of magnitude to approximately 0.1 %. Additionally, I establish a correlation between conductivity of the metal oxide and photocurrent. Preliminary strategies to exceed the current efficiency record of approximately 0.4 % with α-Fe₂O₃ including, increasing the surface area of the photoanode by nanostructuring and optically manipulating incident light using metallic contacts, are discussed.  Additional results are presented for another earth abundant photoanode material, SiC.  The stability of n-type 6H-SiC in a pH=7 buffer and the effect of applying a Pt catalyst to the surface is presented.  Finally, I will also discuss my future teaching and outreach plans at this poster session.

Education

• Center for Nanoscale Science and Technology, (2011-Present)

      National Institute of Standards and Technology

      Advisor: Dr. Veronika Szalai

• University of Cambridge, (2006-2010)

      PhD with Gates Cambridge Scholarship

      Advisor: Prof. J.S. Dennis

• Princeton University, (2002-2006)

      BSE with honors

 Recent Publications:

1. Bohn, C.D.; Agrawal, A.K.; Walter, E.C.; Vaudin, M.D.; Herzing, A.A.; Haney, P.M.; Talin, A.A.; Szalai†, V.A. Effect of tin doping on α-Fe2O3 photoanodes for water splitting. J. Phys. Chem. C 116, 15290–15296 (2012).
2. Bohn, C.D.; Scott, S.A.; Dennis, J.S.; Müller, C.R. Validation of a lattice Boltzmann model for gas–solid reactions with experiments. J. Comput. Phys. 231, 5334–5350 (2012).
3. Bohn, C.D.; Cleeton, J.P.E.; Müller, C.R.; Davidson, J.F.; Hayhurst, A.N.; Scott, S.A.; Dennis, J.S. The kinetics of the reduction of iron oxide by carbon monoxide mixed with carbon dioxide. AIChE J. 56, 1016–1029 (2010).
4. Bohn, C.D.; Cleeton, J.P.E.; Müller, C.R.; Scott, S.A.; Dennis, J.S. Stabilizing iron oxide used in cycles of reduction and oxidation for hydrogen production. Energy Fuels. 24, 4025–4033 (2010).