TiO₂ Nanotubes Decorated with Mo₂C for Enhanced Photoelectrochemical Water-Splitting Properties.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Titanium dioxide (TiO2) nanotube arrays (NTs) show promise for photoelectrochemical (PEC) water splitting.
• Enhancing TiO2 NTs with Ti3+ has previously improved PEC performance.
• Further optimization is needed for efficient and sustainable hydrogen production.

Purpose of the Study:

• To develop an improved photoelectrode for PEC water splitting.
• To investigate the effect of molybdenum carbide (Mo2C) decoration on TiO2 NTs.
• To enhance the hydrogen production efficiency of TiO2-based photoelectrodes.

Main Methods:

• Fabrication of TiO2 NTs via two-step electrochemical anodization and annealing at 450 °C.
• Decoration of TiO2 NTs with Mo2C using dip-coating with varying precursor concentrations and times.
• Characterization using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy.

Main Results:

• XRD confirmed the presence of anatase TiO2 and Ti3O5 phases.
• Mo2C decorated TiO2 NTs achieved a photocurrent density of ~1.4 mA cm-2, a fivefold increase over bare TiO2 NTs (~0.21 mA cm-2).
• FESEM, XPS, and UV-Vis confirmed successful Mo2C deposition and its impact on material properties.

Conclusions:

• Mo2C acts as an effective cocatalyst, significantly enhancing the photocatalytic activity of TiO2 NTs.
• The developed Mo2C-decorated TiO2 NTs offer a promising route for efficient, sustainable hydrogen production via PEC water splitting.
• This approach advances the development of environmentally friendly PEC systems.