C₇N₆/Sc₂CCl₂ Weak van der Waals Heterostructure: A Promising Visible-Light-Driven Z-Scheme Water Splitting...

Area of Science:

• Materials Science
• Photocatalysis
• Computational Chemistry

Background:

• Designing efficient direct Z-scheme photocatalysts for solar water splitting remains a significant challenge.
• Theoretical and experimental characterization is crucial for understanding photocatalyst performance.

Purpose of the Study:

• To theoretically design and characterize a novel mediator-free direct Z-scheme photocatalyst.
• To investigate the light-harvesting and charge separation properties of the proposed heterostructure for solar water splitting.

Main Methods:

• Extensive first-principles calculations.
• Excited state dynamics simulations.
• Analysis of interfacial non-adiabatic coupling and redox capacities.

Main Results:

• A weak van der Waals (vdW) C7N6/Sc2CCl2 heterostructure was identified as a promising direct Z-scheme photocatalyst.
• The heterostructure exhibits excellent light-harvesting capabilities extending into the near-infrared region.
• Strong interfacial non-adiabatic coupling facilitates rapid carrier recombination, while separated electrons and holes drive hydrogen and oxygen evolution reactions.

Conclusions:

• The C7N6/Sc2CCl2 heterostructure is a viable mediator-free direct Z-scheme photocatalyst for efficient solar water splitting.
• The material demonstrates spontaneous hydrogen evolution on C7N6 and oxygen evolution on Se-doped Sc2CCl2 surfaces.
• This work provides a theoretical foundation for developing advanced photocatalysts for sustainable energy applications.