Integrated Catalyst ZnNC⊂PtZn for High-Performance Ethanol Electrooxidation and DEFC

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrocatalysis is crucial for energy conversion technologies.
• Efficient ethanol electrooxidation is key for direct ethanol fuel cells.
• Developing catalysts with high activity and stability remains a challenge.

Purpose of the Study:

• To design and synthesize a novel electrocatalyst for superior ethanol electrooxidation.
• To investigate the structure-activity relationship of the designed catalyst.
• To evaluate the catalyst's performance in an acidic direct ethanol fuel cell.

Main Methods:

• Synthesis of a nest-type electrocatalyst (ZnNC⊂PtZn/C) with a unique inner-outer configuration.
• Electrochemical characterizations including cyclic voltammetry and chronoamperometry.
• Density functional theory (DFT) calculations to understand reaction mechanisms.
• Fuel cell testing to assess power output and stability.

Main Results:

• The ZnNC⊂PtZn/C catalyst exhibited a mass activity of 3.7 A mg_Pt^-1 and 78.2% Faradaic efficiency via the C1 pathway.
• High-energy stepped facets of PtZn nanoparticles, confined by the Zn-N_xC nest, facilitated C-C bond cleavage.
• The catalyst demonstrated excellent stability, retaining 97% of its initial activity after 5,000 cycles.
• The unique structure mitigated concentration polarization, leading to significant power output in an acidic direct ethanol fuel cell.

Conclusions:

• The nest-type electrocatalyst with inner-outer synergistic interactions shows exceptional performance for ethanol electrooxidation.
• The catalyst's design effectively promotes C-C bond cleavage and enhances fuel cell efficiency.
• This work offers a promising strategy for developing advanced electrocatalysts for clean energy applications.