Materializing efficient methanol oxidation via electron delocalization in nickel hydroxide nanoribbon

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Direct methanol fuel cells (DMFCs) require efficient methanol oxidation catalysts.
• Platinum-based catalysts are effective but costly.
• Non-platinum group metal catalysts, like nickel hydroxide (Ni(OH)2), face challenges due to high oxidation potentials.

Purpose of the Study:

• To develop a cost-effective and durable non-platinum catalyst for methanol oxidation in DMFCs.
• To overcome the high initial oxidation potential barrier of traditional Ni(OH)2 catalysts.
• To enable practical DMFC operation by lowering the catalyst's onset potential.

Main Methods:

• Synthesis of periodically arranged four-six-coordinated nickel hydroxide nanoribbons (NR-Ni(OH)2).
• Electrochemical characterization of the catalyst's methanol oxidation activity.
• Analysis of electronic structure and coordination of nickel atoms.

Main Results:

• The NR-Ni(OH)2 catalyst exhibits remarkable methanol oxidation activity.
• An exceptionally low onset potential of 0.55 V vs. RHE was achieved.
• The four-coordinated nickel atoms facilitate charge-transfer orbitals via electron delocalization.

Conclusions:

• The developed NR-Ni(OH)2 structure offers a viable pathway for high-performance, durable, and cost-effective DMFCs.
• This strategy addresses the limitations of traditional Ni(OH)2 catalysts.
• The findings pave the way for advancing non-platinum-based fuel cell technology.