Adsorption Structure of Protonated Melamine on Single Crystal Pt Surfaces

Area of Science:

• Electrochemistry
• Surface Science
• Materials Science

Background:

• Platinum (Pt) electrodes are crucial for catalyzing the oxygen reduction reaction (ORR).
• Melamine has been shown to significantly activate Pt electrodes for ORR.
• A detailed understanding of melamine's activation mechanism is needed to discover new organic additives for ORR enhancement.

Purpose of the Study:

• To investigate the coadsorption structure of water and melamine on single-crystal Pt surfaces.
• To model the adsorption structure of protonated melamine under acidic conditions.
• To evaluate the ORR activity of melamine-modified Pt electrodes prepared via electrospray.

Main Methods:

• Infrared spectroscopy under ultrahigh vacuum (UHV) conditions.
• Electrospray method for dosing protonated melamine onto Pt surfaces.
• Electrochemical evaluation of ORR activity on modified Pt electrodes.

Main Results:

• The orientation of adsorbed melamine is influenced by the Pt substrate's atomic arrangement and the presence of water.
• ORR kinetic current density on electrosprayed melamine-modified Pt electrodes is comparable to conventionally modified electrodes.
• The adsorption structure achieved by electrospray is similar to that of the wetting modification method.

Conclusions:

• The electrospray method effectively prepares melamine-modified Pt electrodes for ORR.
• The findings provide insights into melamine's adsorption behavior on Pt surfaces.
• This study contributes to understanding organic additive effects on ORR catalysis.