Chemical-Dealloying-Derived PtPdPb-Based Multimetallic Nanoparticles: Dimethyl Ether Electrocatalysis and Fuel Cell...

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Direct dimethyl ether (DME) fuel cells offer a promising alternative energy source.
• Developing efficient and cost-effective catalysts is crucial for advancing DME fuel cell technology.

Purpose of the Study:

• To synthesize and characterize a novel multimetallic nanoparticle catalyst (Pt-Pd-Pb) for DME oxidation.
• To investigate the effect of chemical dealloying on catalyst structure and electrochemical activity.
• To evaluate the catalyst's performance in a direct DME fuel cell.

Main Methods:

• Synthesis of Pt-Pd-Pb/C nanoparticles.
• Chemical dealloying using nitric acid (HNO3).
• Comprehensive material characterization (e.g., nanoparticle size, composition, phase analysis).
• Electrochemical testing in liquid and polymer electrolyte fuel cells, including online mass spectrometry.

Main Results:

• Chemical dealloying of Pt2PdPb2/C removed 50% of Pb, forming smaller nanoparticles with Pt, Pt3Pb, and PtPb phases.
• The dealloyed catalyst exhibited significantly enhanced electrochemical activity for DME oxidation.
• Achieved a high PGM-normalized power density of 118 mW mgPGM−1 at low catalyst loading (1 mgPGM cm−2) and 70 °C.

Conclusions:

• Chemical dealloying is an effective strategy to tune the activity of multimetallic catalysts for DME oxidation.
• The resulting multimetallic catalyst demonstrates excellent performance for direct DME fuel cells.
• The study proposes a plausible DME oxidation pathway over these novel catalysts.