Modulating Co-catalyst/Facet Junction for Enhanced Photoelectrochemical Water Splitting

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Improving photogenerated charge separation is key for efficient solar energy conversion.
• Fermi-level pinning from co-catalyst strategies can hinder photoelectrochemical performance.

Purpose of the Study:

• To investigate the effect of co-catalyst deposition on different anisotropic facets of titanium dioxide nanorods.
• To enhance photoanode catalytic activity and solar energy conversion efficiency.

Main Methods:

• Electrodeposition of manganese dioxide onto specific (111) and (110) facets of titanium dioxide nanorods.
• Photoelectrochemical measurements to evaluate photocurrent density and photovoltage.
• Analysis of interface electric field strength and photovoltage decay.

Main Results:

• Manganese dioxide on the (111) facet significantly boosted photoanode activity compared to the (110) facet.
• Achieved a photocurrent density of 1.65 mA·cm^-2 at 1.23 V, near the theoretical maximum for titanium dioxide.
• Demonstrated a 95.15% charge separation efficiency with reduced photovoltage decay.

Conclusions:

• Facet-dependent co-catalyst loading is crucial for optimizing charge separation and photoelectrochemical performance.
• Stronger interface electric fields and minimized photovoltage decay contribute to enhanced solar energy conversion.
• This study provides insights for designing efficient photocatalysts by controlling co-catalyst-substrate interactions.