Constructing a visible-light-excited Z-scheme heterojunction by engineering the directional N-C/Cu insertion layer:...

Area of Science:

• Materials Science
• Photocatalysis
• Heterojunction Engineering

Background:

• S-scheme heterojunctions are crucial for efficient photocatalysis.
• Work function matching between semiconductors limits material selection in heterojunctions.

Purpose of the Study:

• To overcome work function mismatch limitations in constructing S-scheme heterojunctions.
• To develop an interfacial engineering strategy for Z-scheme photocatalysts.

Main Methods:

• Fabrication of a WO3/N-C/Cu/Cu2O heterojunction using post-deposition and pyrolysis.
• Introduction of a nitrogen-doped carbon (N-C) mediator and Cu nanoparticles.
• Characterization using femtosecond transient absorption spectroscopy and electron paramagnetic resonance.

Main Results:

• The WO3/N-C/Cu/Cu2O heterojunction successfully preserved the redox potentials of WO3 and Cu2O.
• Efficient charge carrier transfer and recombination redirection were observed.
• Achieved 99% yield in alkyne homo-coupling and a 300-fold increase in hydrogen evolution rate.

Conclusions:

• The N-C mediator and Cu nanoparticles effectively enable Z-scheme construction with mismatched semiconductors.
• This interfacial engineering approach provides a universal paradigm for designing advanced photocatalytic systems.
• The developed heterojunction shows significant potential for solar energy conversion and organic synthesis.