Elucidating Carrier Dynamics and Interface Engineering in Sb₂S₃: Toward Efficient Photoanode for Water Oxidation

Area of Science:

• Materials Science
• Photochemistry
• Renewable Energy

Background:

• Solar-driven photoelectrochemical (PEC) energy conversion requires efficient semiconductor materials.
• Antimony trisulfide (Sb2S3) is a promising wide-bandgap semiconductor for PEC water splitting.
• Bulk Sb2S3 suffers from charge recombination and poor charge separation, limiting its performance.

Purpose of the Study:

• To investigate the carrier dynamics in Sb2S3 using ultrafast spectroscopy.
• To design and fabricate a SnO2/Sb2S3 heterojunction to improve charge separation efficiency.
• To evaluate the photoelectrochemical water oxidation performance of the SnO2/Sb2S3 photoanode.

Main Methods:

• Ultrafast spectroscopy was employed to clarify carrier dynamics.
• A heterojunction was designed between Sb2S3 and SnO2 with optimized band-edge alignment.
• The SnO2/Sb2S3 photoanode was fabricated using vapor deposition techniques.

Main Results:

• The SnO2/Sb2S3 heterojunction demonstrated enhanced charge separation efficiency.
• The fabricated photoanode achieved a photocurrent density of approximately 3 mA cm-2 at 1.38 V vs RHE.
• Vapor deposition enabled the fabrication of the SnO2/Sb2S3 photoanode.

Conclusions:

• The SnO2/Sb2S3 heterojunction effectively improves photocurrent generation in PEC water splitting.
• Optimizing semiconductor interfaces is crucial for advancing solar energy conversion technologies.
• This work presents a viable approach for developing efficient photoanodes for water oxidation.