Gold nanoparticle-based supramolecular approach for dye-sensitized H₂-evolving photocathodes

Area of Science:

• Materials Science
• Photochemistry
• Catalysis

Background:

• Photoelectrochemical water splitting is a key technology for renewable energy.
• Efficient hydrogen production requires advanced photocathode materials.

Purpose of the Study:

• To develop a novel photocathode nanohybrid system for efficient solar water splitting.
• To investigate a supramolecular approach for linking dye sensitizers and reduction catalysts.

Main Methods:

• Fabrication of a dye-sensitized p-type nickel oxide (NiO) photocathode.
• Incorporation of a perylene-based chromophore (PCA) and a cobaloxime reduction catalyst (Co).
• Utilizing β-cyclodextrin functionalized gold nanoparticles (β-CD-AuNPs) for supramolecular linkage.

Main Results:

• Demonstrated ultrafast hole injection from the excited dye into NiO (π = 3 ps).
• Observed rapid reduction of the cobaloxime catalyst.
• Confirmed efficient hydrogen (H₂) evolution upon irradiation.

Conclusions:

• The novel NiO|PCA|β-CD-AuNPs|Co architecture enables efficient photo-reduction of protons to H₂.
• The supramolecular linkage is crucial for the system's performance.
• This work advances the development of materials for solar fuel production.