Symmetrical waveform alternating current driven electron enrichment for enhanced oxygen evolution reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is crucial for many energy conversion technologies.
• Developing efficient and stable electrocatalysts for OER remains a significant challenge.
• Current methods for catalyst activation often involve harsh conditions or complex procedures.

Purpose of the Study:

• To develop a novel activation method for NiFeO_xH_y electrocatalysts.
• To investigate the effect of symmetrical alternating current activation on OER performance.
• To understand the underlying mechanisms responsible for performance enhancement.

Main Methods:

• Symmetrical-waveform alternating current (AC) pulses were used for *in situ* activation of NiFeO_xH_y.
• Electrochemical characterization techniques were employed to evaluate OER activity and stability.
• Surface analysis was performed to understand the structural and electronic changes in the catalyst.

Main Results:

• AC activation created electron-enriched NiFeO_xH_y lattices.
• The engineered catalyst exhibited improved intermediate adsorption, conductivity, and mass transport.
• A 33.8% higher current density was achieved at 2.3 V *vs.* RHE compared to untreated catalysts.
• The activated catalyst demonstrated excellent stability over 200 hours.

Conclusions:

• Symmetrical-waveform AC activation is an effective strategy for enhancing NiFeO_xH_y electrocatalysts.
• The electron-enriched lattice structure is key to the improved OER performance.
• This activation method offers a promising route for developing advanced OER catalysts.