Pt-Modified High Entropy Rare Earth Oxide for Efficient Hydrogen Evolution in pH-Universal Environments.

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Efficient and stable catalysts are crucial for hydrogen production via water electrolysis to address the energy crisis.
• Developing catalysts that operate effectively across a wide pH range remains a significant challenge.

Purpose of the Study:

• To develop novel platinum nanoparticles (Pt NPs) anchored on high entropy rare earth oxides (HEREOs) for highly efficient hydrogen production.
• To investigate the electrochemical performance and stability of these new catalysts in various pH environments.

Main Methods:

• Synthesis of Pt NPs anchored on HEREOs (specifically Pt-(LaCeSmYErGdYb)O).
• Electrochemical characterization including overpotential measurements for 100 mA cm⁻² current density in acidic, alkaline, and neutral electrolytes.
• Durability testing at high current density and elevated temperature.
• Density functional theory (DFT) calculations to understand the catalytic mechanism.

Main Results:

• The Pt-HEREO catalyst demonstrated excellent performance, requiring low overpotentials (12 mV in H₂SO₄, 57 mV in KOH, 77 mV in PBS) for 100 mA cm⁻².
• Exceptional stability was observed, operating at 400 mA cm⁻² at 60 °C for 100 hours in acidic media.
• Achieved high mass activity (37.7 A mg⁻¹Pt) and turnover frequency (38.2 s⁻¹), surpassing existing hydrogen evolution reaction (HER) catalysts.
• DFT calculations revealed optimized electronic structures and intermediate binding due to Pt-HEREO interactions.

Conclusions:

• Pt NPs anchored on HEREOs represent a highly efficient and robust electrocatalyst for hydrogen evolution reaction (HER) in diverse pH conditions.
• The synergistic effect between Pt and HEREOs enhances electron transfer and optimizes reaction kinetics.
• This study offers a new strategy for designing advanced rare-earth-based electrocatalysts for sustainable hydrogen production.