All-Solution-Processed WO₃/BiVO₄ Core-Shell Nanorod Arrays for Highly Stable Photoanodes

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Tungsten oxide (WO3) and bismuth vanadate (BiVO4) are promising materials for photoelectrochemical (PEC) applications.
• Efficient heterojunctions are crucial for improving charge carrier dynamics and light absorption in PEC devices.

Purpose of the Study:

• To develop an all-solution-processed WO3/BiVO4 heteronanostructure photoanode.
• To enhance photoactivity and stability for sustainable energy production.
• To investigate the underlying mechanisms for improved PEC performance.

Main Methods:

• Vertically aligned WO3 nanorods synthesized via a hydrothermal method.
• Conformal coating of BiVO4 using pulsed electrodeposition.
• Fabrication of WO3/BiVO4 heteronanostructure on fluorine-doped tin oxide/glass substrates.

Main Results:

• The optimized WO3/BiVO4 photoanode achieved a photocurrent density of 4.15 mA/cm2 at 1.23 V vs RHE.
• Incident-photon-to-current efficiency (IPCE) reached 75.9% at 430 nm under front illumination.
• Performance metrics were significantly enhanced compared to pristine WO3 nanorod arrays.

Conclusions:

• The WO3/BiVO4 heteronanostructure exhibits superior photoactivity and stability.
• The developed all-solution process is environmentally friendly and cost-effective.
• This work provides a viable route for synthesizing high-quality photoelectrodes for PEC applications.