Surface Engineering of Anodic WO₃ Layers by In Situ Doping for Light-Assisted Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Tungsten oxide (WO3) is a promising material for photocatalysis.
• Improving the photoelectrochemical (PEC) performance of WO3 is crucial for applications like solar water splitting.
• Doping WO3 can enhance its properties, but controlled synthesis methods are needed.

Purpose of the Study:

• To develop a novel single-step electrochemical synthesis for anodic Co-F-WO3 layers.
• To investigate the effect of cobalt and fluorine doping on WO3 properties.
• To evaluate the PEC performance of Co-F-WO3 for solar water splitting and the oxygen evolution reaction (OER).

Main Methods:

• Single-step electrochemical synthesis of anodic Co-F-WO3.
• Characterization using EDS, XRD, Raman, photoluminescence, XPS, and Mott-Schottky analysis.
• Photoelectrochemical measurements to assess PEC activity and stability for OER.

Main Results:

• Successfully synthesized nanoporous Co-F-WO3 layers with in situ doping.
• Confirmed doping and incorporation of cobalt and fluorine using various spectroscopic techniques.
• Observed lower absorption and slight band gap shifts in Co-doped materials.
• Demonstrated significantly enhanced PEC activity (up to 5-fold) for Co-F-WO3 in solar water splitting and OER.
• Showcased reusability of the photoanodes for PEC water-splitting experiments.

Conclusions:

• The single-step electrochemical synthesis is effective for producing Co-F-WO3 photoanodes.
• Co-F doping enhances the PEC activity of WO3 for solar water splitting and OER.
• The developed Co-F-WO3 layers show potential as efficient and reusable photoelectrodes.