An effective Pd-Ni(2)P/C anode catalyst for direct formic acid fuel cells

Area of Science:

• Electrochemistry
• Materials Science
• Energy Conversion

Background:

• Direct formic acid fuel cells (DFAFCs) are promising energy conversion devices.
• Palladium (Pd) is the benchmark anode catalyst for formic acid oxidation in DFAFCs.
• Improving Pd catalyst activity and stability remains a critical challenge for DFAFC commercialization.

Purpose of the Study:

• To enhance the catalytic performance of palladium for formic acid oxidation.
• To investigate the use of nickel phosphide (Ni(2)P) nanoparticles as a co-catalyst with palladium.
• To evaluate the impact of Pd-Ni(2)P co-catalysts on DFAFC performance.

Main Methods:

• Synthesis and characterization of palladium-nickel phosphide (Pd–Ni(2)P) co-catalyst nanoparticles.
• X-ray photoelectron spectroscopy (XPS) to analyze electronic interactions between Pd and Ni(2)P.
• Fabrication and electrochemical testing of DFAFCs utilizing the developed co-catalyst.

Main Results:

• Significant enhancement in the activity and stability of palladium for formic acid oxidation was observed with Ni(2)P co-catalysis.
• XPS analysis confirmed a strong electronic interaction between Ni(2)P and Pd, contributing to improved performance.
• The optimized Pd–Ni(2)P anode catalyst achieved a power density of 550 mWcm(-2) in a DFAFC, a 3.5-fold increase over commercial Pd catalysts.

Conclusions:

• Nickel phosphide nanoparticles effectively enhance the catalytic properties of palladium for formic acid oxidation.
• The strong electronic interaction between Pd and Ni(2)P is key to the improved catalytic activity and stability.
• The developed Pd–Ni(2)P co-catalyst represents a significant advancement for direct formic acid fuel cell technology.