Rare-earth oxide promoted Pd electrocatalyst for formic acid oxidation

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Direct formic acid fuel cells (DFAFCs) require efficient anode catalysts for practical application.
• Palladium (Pd)-based materials are promising but need improved activity and stability.
• Formic acid oxidation (FAO) is a key reaction in DFAFCs, often hindered by CO poisoning.

Purpose of the Study:

• To investigate the enhancement of Pd catalyst performance for FAO using rare-earth oxides.
• To synthesize and characterize Pd nanoparticles incorporated with Sc2O3 on nitrogen-doped reduced graphene oxide (N-rGO).
• To evaluate the electrocatalytic activity, stability, and CO tolerance of the developed catalysts.

Main Methods:

• Synthesis of Pd-Sc2O3/N-rGO catalysts using a sodium borohydride reduction method.
• Characterization of catalyst composition and structure.
• Electrochemical evaluation of formic acid oxidation (FAO) using cyclic voltammetry and chronoamperometry.

Main Results:

• Pd-Sc2O3/N-rGO-2/3 exhibited a high mass current density of 972.9 mA mgPd−1 for FAO.
• This performance significantly surpassed reference catalysts Pd/C (262.6 mA mgPd−1) and Pd/N-rGO (304.9 mA mgPd−1).
• The Pd-Sc2O3/N-rGO-2/3 catalyst demonstrated excellent CO tolerance and long-term stability.

Conclusions:

• Incorporation of Sc2O3 with Pd nanoparticles on N-rGO synergistically enhances catalytic activity for FAO.
• The developed Pd-Sc2O3/N-rGO catalyst shows great potential for direct formic acid fuel cell applications.
• This study highlights the role of rare-earth oxides in advancing Pd-based electrocatalysts.