Boosting Alkaline Oxygen Evolution Kinetics by Tailoring the Noncovalent Interaction on CoOOH

Area of Science:

• Electrochemistry
• Surface Science
• Materials Science

Background:

• Improving electrocatalytic reaction kinetics is crucial for energy conversion technologies.
• Understanding interfacial phenomena at the catalyst-electrolyte interface is key to optimizing performance.

Purpose of the Study:

• To investigate the effect of carboxylate anions on the oxygen evolution reaction (OER) kinetics at a cobalt oxyhydroxide (CoOOH) catalyst.
• To elucidate the role of noncovalent interactions and the electronic double layer (EDL) in modulating OER performance.

Main Methods:

• Cobalt oxyhydroxide (CoOOH) as a model catalyst.
• Carboxylate-based additives to modulate the interfacial electronic double layer (EDL).
• Experimental techniques: Rotating Ring-Disk Electrode (RRDE), in situ X-ray Absorption Spectroscopy (XAS), in situ Attenuated Total Reflectance Surface-Enhanced Infrared Absorption Spectroscopy (ATR-SEIRAS).
• Theoretical simulations: Ab initio Molecular Dynamics (AIMD).

Main Results:

• Carboxylate anions disrupt the hydration shell of K+ ions via hydrogen bonding.
• This disruption facilitates the migration of hydroxide anions (OH-) to the catalyst surface.
• The negative potential of carboxylate groups neutralizes the electric field, destabilizing intermediates and accelerating deprotonation.
• Promoted charge accumulation and accelerated alkaline OER kinetics were observed.

Conclusions:

• Carboxylate additives effectively enhance alkaline OER kinetics by manipulating interfacial properties.
• Noncovalent interactions play a significant role in optimizing electrocatalyst performance.
• The findings provide insights into designing advanced electrocatalysts for efficient energy conversion.