Efficient Synthesis and Catalytic Performance Tuning of High-Entropy Alloys Using a Weaving Strategy

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• High-entropy alloys (HEAs) show promise in catalysis due to multiple active sites and synergistic metal interactions.
• High-entropy metal-organic frameworks (HE-MOFs) are effective precursors for HEA synthesis.
• Current HE-MOF synthesis methods face challenges with complex kinetics due to diverse metal ions.

Purpose of the Study:

• To develop a novel strategy for synthesizing HE-MOFs with improved control over reaction kinetics.
• To create HEAs with tunable compositions and enhanced catalytic properties using HE-MOFs.
• To demonstrate the application of these HEAs in photocatalytic hydrogen evolution.

Main Methods:

• A weaving strategy using pre-synthesized metal-ligand complexes (MLs) as modular building blocks.
• Fabrication of HE-MOFs with cerium oxide clusters as structural nodes.
• Carbonization and reduction of HE-MOFs to produce CeO2/C-supported HEAs.

Main Results:

• Successful synthesis of HE-MOFs using the ML weaving strategy, overcoming coordination complexities.
• Conversion of HE-MOFs into CeO2/C-supported HEAs with adjustable metal content.
• Optimized HEA catalyst achieved a hydrogen evolution rate of 13.4 mmol g-1 h-1 in a dye-sensitized photocatalytic system.

Conclusions:

• The novel weaving strategy offers atomic-level control over HEA metal composition.
• Homogeneous distribution of diverse metal ions in HEAs is achievable.
• This approach enables the rational design of highly efficient catalytic systems, particularly for hydrogen evolution.