Interlayer Charge Transfer Regulates Single-Atom Catalytic Activity on Electride/Graphene 2D Heterojunctions.

Area of Science:

• Materials Science
• Catalysis
• Surface Chemistry

Background:

• Single-atom catalysts (SACs) are crucial for energy and environmental applications due to their tunable structure and activity.
• Developing efficient SACs requires understanding and controlling metal-atom interactions at the catalytic surface.

Purpose of the Study:

• To investigate the catalytic properties of single-atom catalysts supported on two-dimensional (2D) graphene and electride heterostructures.
• To explore the role of interfacial charge transfer in tuning the activity of SACs for key chemical reactions.

Main Methods:

• First-principles calculations were employed to study SACs on 2D graphene-electride heterostructures.
• Analysis of electron transfer from electride layers to graphene and its effect on metal atom d-orbital occupancy.
• Development of a polynomial regression model to correlate charge variation with adsorption energy.

Main Results:

• Electride layers facilitate colossal, controllable electron transfer to graphene, significantly influencing the electronic structure of supported single metal atoms.
• Enhanced catalytic activity for hydrogen evolution reactions (HER) and oxygen reduction reactions (ORR) was observed.
• A strong correlation between adsorption energy (Eads) and charge variation (Δq) was established, identifying interfacial charge transfer as a key descriptor.
• The regression model accurately predicted adsorption energies, validating the importance of charge transfer.

Conclusions:

• Graphene-electride heterostructures offer a novel platform for designing high-efficiency single-atom catalysts.
• Interfacial charge transfer is a critical factor in optimizing SAC performance for energy and environmental catalysis.
• This work provides a theoretical strategy for developing advanced SACs through rational heterostructure design.