Facile Integration between Si and Catalyst for High-Performance Photoanodes by a Multifunctional Bridging Layer.

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• High-performance photoelectrochemical (PEC) water-splitting devices require optimized interfaces.
• Silicon-based photoanodes are promising for solar water splitting but face challenges with stability and efficiency.

Purpose of the Study:

• To design and demonstrate a facile interface for efficient photoelectrochemical water oxidation.
• To improve charge transfer and stability at the semiconductor/catalyst interface.

Main Methods:

• Integration of polycrystalline n⁺p-Si with NiFe-layered double hydroxide (LDH) nanosheet arrays.
• Utilizing a partially activated Ni (Ni/NiO_x) bridging layer.
• Employing a back illumination configuration.

Main Results:

• Achieved an onset potential of ~0.78 V vs. RHE and a photocurrent density of ~37 mA cm^-2 at 1.23 V vs. RHE.
• Demonstrated excellent stability in 1.0 M KOH.
• Reported the highest water oxidation activity for crystalline Si-based photoanodes to date.

Conclusions:

• The Ni/NiO_x bridging layer effectively facilitates charge transfer and ensures robust contact.
• This strategy offers a simple and efficient approach for enhancing PEC water-splitting performance.
• The developed earth-abundant multicomponent photoanode shows significant potential for solar water splitting.