Modifying Ti-Based Gas Diffusion Layer Passivation for Polymer Electrolyte Membrane Water Electrolysis via...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Gas diffusion layers (GDLs) are critical components in polymer electrolyte membrane (PEM) water electrolyzers (WE).
• Titanium-based GDLs offer stability but suffer from passivation, limiting their use.
• Improving GDL reliability is essential for efficient and durable PEM water electrolysis.

Purpose of the Study:

• To develop an inexpensive method for enhancing the conductivity and corrosion resistance of titanium-based GDLs.
• To investigate the effects of electrochemical nitridation on the surface properties of Ti-based GDLs.
• To assess the performance of modified Ti-based GDLs in simulated PEM WE environments.

Main Methods:

• Electrochemical nitridation of Ti felt GDLs.
• Controlled adjustment of reduction potential and reaction time.
• Surface characterization using X-ray photoelectron spectroscopy (XPS).
• Measurement of interfacial contact resistance and corrosion resistance.

Main Results:

• Electrochemical nitridation successfully formed a TiN/TiO nitride phase on the Ti felt surface.
• The modified GDL exhibited low interfacial contact resistance (1.0 mΩ cm² at 140 N/cm²).
• The TiN/TiO surface demonstrated excellent corrosion resistance (0.920 μA cm^-2).

Conclusions:

• Electrochemical nitridation is an economical and effective method for improving Ti-based GDLs.
• The enhanced GDLs show high performance, promising for efficient PEM water electrolysis.
• This approach addresses reliability issues associated with titanium GDLs in WE applications.