SmCo₅ with a Reconstructed Oxyhydroxide Surface for Spin-Selective Water Oxidation at Elevated Temperature

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrolytic hydrogen production efficiency is hindered by slow oxygen evolution reaction (OER) kinetics.
• Surface-reconstructed ferromagnetic (FM) catalysts offer potential OER enhancement via spin-pinning effects.
• Elevated operating temperatures in electrolyzers can negatively impact FM catalyst performance.

Purpose of the Study:

• To investigate the OER activity of surface-reconstructed SmCo5/CoOₓH<0xE1><0xB5><0xA7> catalysts.
• To explore the effect of magnetization on OER performance.
• To assess catalyst stability at elevated temperatures relevant to industrial applications.

Main Methods:

• Preparation of surface-reconstructed SmCo5/CoOₓH<0xE1><0xB5><0xA7> catalysts.
• Characterization of interfacial spin polarization.
• Electrochemical testing of OER activity under varying temperatures.
• Magnetization process to align interfacial spins.

Main Results:

• The SmCo5/CoOₓH<0xE1><0xB5><0xA7> catalyst exhibited excellent OER activity due to polarized spins at the FM/oxyhydroxide interface.
• Magnetization further enhanced the OER performance by aligning interfacial spins.
• The enhanced OER activity was maintained up to 60°C, demonstrating thermal stability.

Conclusions:

• Surface-reconstructed SmCo5/CoOₓH<0xE1><0xB5><0xA7> with interfacial spin polarization is a promising catalyst for efficient OER.
• Magnetization is an effective strategy to boost OER performance.
• The catalyst's thermal stability suggests its viability for practical water electrolysis applications.