Photoelectrochemical Behavior of n-Type Si(111) Electrodes Coated With a Single Layer of Graphene
Abstract
The behavior of graphene-coated n-type Si(111) photoanodes was compared to the behavior of H-terminated n-type Si(111) photoanodes in contact with aqueous K₃[Fe(CN)₆]/K₄[Fe(CN)₆] as well as in contact with a series of outer-sphere, one-electron redox couples in nonaqueous electrolytes. The n-Si/Graphene electrodes exhibited stable short-circuit photocurrent densities of over 10 mA cm⁻² for >1000 s of continuous operation in aqueous electrolytes, whereas n-Si–H electrodes yielded a nearly complete decay of the current density within ∼100 s. The values of the open-circuit photovoltages and the flat-band potentials of the Si were a function of both the Fermi level of the graphene and the electrochemical potential of the electrolyte solution, indicating that the n-Si/Graphene did not form a buried junction with respect to the solution contact.
Additional Information
N.S.L. and A.C.N. acknowledge the NSF, Grant CHE-1214152, for support and the Beckman Institute Molecular Materials Resource Center for facilities. A.C.N. acknowledges support from the Dept. of Defense through the National Defense Science & Engineering Graduate Fellowship Program. S.A. acknowledges support from a U.S. Dept. of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under EERE Fuel Cell Technologies Program. N.P. and J.H. acknowledge the Center for Re-Defining Photovoltaic Efficiency Through Molecular-Scale Control, an Energy Frontier Research Center funded by the U.S. Dept. of Energy, Office of Science, Office of Basic Energy Sciences under Award DE-SC0001085.Additional details
- Eprint ID
- 117441
- Resolver ID
- CaltechAUTHORS:20221017-72823300.1
- CHE-1214152
- NSF
- National Defense Science and Engineering Graduate (NDSEG) Fellowship
- DE-SC0001085
- Department of Energy (DOE)
- Created
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2022-10-20Created from EPrint's datestamp field
- Updated
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2022-10-20Created from EPrint's last_modified field