Enhanced Photoelectrochemical Performance Using Cobalt-Catalyst-Loaded PVD/RF-Engineered WO₃ Photoelectrodes

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Improving photoelectrochemical (PEC) performance requires enhanced visible light absorption, carrier separation, and reduced electron-hole recombination.
• Tungsten oxide (WO3) is a promising material for photoanodes, but its efficiency can be limited by light absorption and charge transfer properties.

Purpose of the Study:

• To investigate the effect of cobalt (Co) nanoparticle modification on WO3 thin films for enhanced PEC performance.
• To explore the potential of non-noble metal catalysts for improving solar energy conversion.

Main Methods:

• Fabrication of WO3 thin films using the Physical Vapor Deposition/Radio Frequency (PVD/RF) method.
• Surface modification of WO3 films with varying concentrations of cobalt nanoparticles.
• Characterization using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, FE-SEM, and HR-TEM.
• Evaluation of optical and PEC properties via UV-vis spectroscopy, linear sweep voltammetry, and electrochemical impedance spectroscopy (EIS).

Main Results:

• Cobalt nanoparticle loading extended the visible light absorption spectrum of WO3 films.
• Enhanced electron capture and accelerated carrier separation were observed in Co/WO3 films.
• A significant increase in photocurrent density (from 1.020 mA/cm² to 1.485 mA/cm²) was achieved compared to pristine WO3.
• Improved interface charge transfer efficiency was confirmed.

Conclusions:

• Cobalt nanoparticles act as effective catalysts, significantly boosting the photoelectrochemical performance of WO3 photoanodes.
• The developed Co/WO3 films demonstrate potential for large-scale, high-performance photoelectrochemical applications.
• This study provides valuable insights for designing efficient photoanodes for solar energy conversion.