The reaction mechanism with free energy barriers at constant potentials for the oxygen evolution reaction at the IrO2 (110) surface
Complex charge transfer processes, high overpotential, and corrosion make it difficult to efficiently oxidize H2O to O2 (Oxygen Evolution Reaction, OER) in photoelectrochemical cells (PEC). So far no OER mechanism has been fully explained atomistically with both thermodynamic and kinetics. IrO2 is the only known OER catalyst with both high catalytic activity and stability in acidic conditions. This is important because PEC experiments often operate at extreme pH conditions. Here, we performed first principles calculations integrated with implicit solvation at constant potentials to examine the detailed atomistic reaction mechanism of OER at the IrO2 (110) surface. We also determined the surface phase diagram, explored the possible reaction pathways including kinetic barriers, and computed reaction rates based on the micro-kinetic models. This allowed us to resolve several long-standing puzzles about the atomistic OER mechanism.
- Research Organization:
- California Institute of Technology (CalTech), Pasadena, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- SC0004993; AC02-05CH11231; SC004993
- OSTI ID:
- 1346958
- Alternate ID(s):
- OSTI ID: 1347420
- Journal Information:
- Journal of the American Chemical Society, Vol. 139, Issue 1; ISSN 0002-7863
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
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