Truncated octahedral Pt(3)Ni oxygen reduction reaction electrocatalysts.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing efficient catalysts is crucial for advancing fuel cell technology.
• Current catalysts often face limitations in activity and cost-effectiveness.
• Optimizing nanoparticle composition, size, and shape is key to enhancing catalytic performance.

Purpose of the Study:

• To synthesize and characterize carbon-supported Pt(3)Ni nanoparticle catalysts.
• To develop an effective surface treatment for removing capping agents in nanoparticle synthesis.
• To evaluate the catalytic activity of these Pt(3)Ni nanoparticles for the oxygen reduction reaction.

Main Methods:

• Solution-phase synthesis of truncated-octahedral Pt(3)Ni nanoparticles.
• Butylamine-based surface treatment to remove alkane-chain capping agents.
• Electrochemical testing to determine area-specific and mass activity for oxygen reduction reaction.

Main Results:

• Achieved high area-specific activity of 850 muA/cm(2)(Pt) at 0.9 V, approximately four times greater than commercial Pt/C.
• Reached mass activity of 0.53 A/mg(Pt) at 0.9 V, a nearly four-fold increase.
• Demonstrated a strong correlation between mass activity and the (111) surface fraction of the nanoparticles.

Conclusions:

• The developed Pt(3)Ni nanoparticle catalysts exhibit superior performance for the oxygen reduction reaction.
• The surface treatment method is effective in preparing highly active nanoparticle catalysts.
• Results validate the importance of surface structure and suggest potential for further improvements in fuel cell catalyst design.