Amorphous (ErAlCrZrTi)O High-Entropy Nanofilms for Highly Efficient Hydrogen Embrittlement Prevention

Area of Science:

• Materials Science
• Nanotechnology
• Corrosion Science

Background:

• Hydrogen embrittlement poses a significant risk to the safety and longevity of hydrogen energy systems.
• Developing effective hydrogen barriers is critical for mitigating this challenge.
• Existing solutions face limitations in efficiency and durability.

Purpose of the Study:

• To fabricate and characterize a novel amorphous high-entropy nanofilm as a hydrogen barrier.
• To evaluate the hydrogen permeability and resistance enhancement provided by the nanofilm.
• To investigate the underlying mechanisms and durability of the hydrogen barrier.

Main Methods:

• Sol-gel fabrication of amorphous (ErAlCrZrTi)O high-entropy nanofilm on steel.
• Measurement of hydrogen permeability and hydrogen resistance at elevated temperatures.
• Assessment of nanofilm performance after irradiation and thermal shock tests.
• Analysis of adhesion strength and interfacial transition layers.
• Theoretical calculations to elucidate the barrier mechanism.

Main Results:

• The 270 nm (ErAlCrZrTi)O nanofilm achieved ultra-low hydrogen permeability (1.35 × 10⁻¹⁵ mol m⁻¹ s⁻¹ Pa⁻⁰.⁵).
• Hydrogen resistance was enhanced by 2738 times at 500 °C compared to bare steel, outperforming individual oxide components.
• The nanofilm maintained high hydrogen resistance after 10 dpa irradiation and exhibited excellent thermal shock resistance and 37 MPa bonding strength.
• A Cr₂O₃ transition layer formed during annealing, enhancing adhesion and mitigating thermal expansion mismatch.

Conclusions:

• The amorphous (ErAlCrZrTi)O high-entropy nanofilm is a highly efficient and robust hydrogen barrier.
• The nanofilm offers superior hydrogen embrittlement prevention for steel in hydrogen energy applications.
• The findings provide insights for designing advanced hydrogen barriers.