MXene Surface Terminations Enable Strong Metal-Support Interactions for Efficient Methanol Oxidation on Palladium

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Efficient methanol oxidation reaction (MOR) is crucial for direct methanol fuel cells.
• Developing effective supports for noble metal catalysts is key to reducing cost and improving activity.

Purpose of the Study:

• To enhance the activity of palladium (Pd) catalysts for MOR using a novel support material.
• To investigate the role of metal-support interactions in catalyst performance.

Main Methods:

• Utilized two-dimensional Ti3C2Tx MXene as a support for palladium nanoparticles.
• Employed spectroscopy and density functional theory (DFT) computations to analyze catalyst structure and electronic properties.
• Evaluated catalyst performance through electrochemical testing of the methanol oxidation reaction.

Main Results:

• Achieved over 60% activity enhancement for Pd/MXene compared to commercial Pd/C.
• Demonstrated increased exposure of catalytically active Pd sites and altered electronic structure.
• Observed significantly higher MOR current density (12.4 mA cm-2) for Pd/MXene versus Pd/C (7.6 mA cm-2).

Conclusions:

• Ti3C2Tx MXene effectively enhances Pd catalyst activity for MOR through strong metal-support interactions (SMSI).
• Electronegative MXene terminations induce optimal methanol adsorption and improved intrinsic catalyst activity.
• This study provides a rational design strategy for developing advanced noble metal catalysts for fuel cell applications.