Spin-Polarized Oxygen Evolution Reaction Enabled by Chiral Molecules Coupled with Ferromagnetic Electrocatalysts

Area of Science:

• Catalysis
• Materials Science
• Electrochemistry

Background:

• Chirality-induced spin selectivity (CISS) enables chiral molecules to act as spin filters for electrons.
• CISS has been applied to energy conversion, particularly the oxygen evolution reaction (OER).
• The precise role of CISS in OER intermediate formation and rate-determining steps (RDS) remains unclear.

Purpose of the Study:

• To investigate how CISS affects intermediate species formation and the RDS in the oxygen evolution reaction.
• To elucidate the mechanism of CISS in electrocatalysis using materials with distinct magnetic properties.

Main Methods:

• Synthesis of ferromagnetic CoFe2O4 and paramagnetic Co3O4 electrocatalysts.
• Electrochemical analysis including Tafel analysis and kinetic isotope effect studies.
• In situ infrared spectroscopy to monitor intermediate species.

Main Results:

• Spin-polarized charge carriers maintained spin alignment with ferromagnetic CoFe2O4.
• In the absence of chiral molecules, O* formation was the RDS.
• Chiral molecules shifted the RDS to include OOH* formation, a key intermediate.

Conclusions:

• CISS plays a critical role in modifying the OER mechanism and intermediate formation.
• The spin selectivity effect can alter the rate-determining step in electrocatalytic reactions.
• Understanding CISS is crucial for optimizing chiral molecule-based energy conversion technologies.