Direct conversion of CO₂ to CH₄ on Pd/graphdiyne single-crystalline

Area of Science:

• Catalysis
• Materials Science
• Renewable Energy

Background:

• Artificial photosynthesis requires efficient and selective photocatalysts for CO2 conversion.
• Current catalysts often lack selectivity or efficiency at room temperature and ambient pressure.

Purpose of the Study:

• To synthesize and characterize a novel graphdiyne-based palladium quantum dot catalyst.
• To investigate its performance in selective artificial photosynthesis for CO2 conversion.

Main Methods:

• Synthesis of graphdiyne-based palladium quantum dot catalysts with high-density metal atom steps.
• Characterization of catalyst interface structure with electron-donor and acceptor groups.
• Mechanism studies involving local surface plasmon resonance and photogenerated carrier separation.

Main Results:

• The catalyst exhibits incomplete charge transfer between graphdiyne and palladium quantum dots.
• Synergistic effects of 'hot electrons' and rapid carrier separation enhance reaction kinetics.
• Selective synthesis of methane (CH4) from CO2 and H2O with near 100% selectivity.
• Achieved an average CH4 yield of 26.2 μmol g-1 h-1 with remarkable long-term stability.

Conclusions:

• The developed catalyst demonstrates transformative performance for artificial photosynthesis.
• The unique interface structure and synergistic effects are key to high efficiency and selectivity.
• This catalyst offers a promising solution for sustainable CO2 conversion at ambient conditions.