Nickel-Regulated Composite Cathode with Balanced Triple Conductivity for Proton-Conducting Solid Oxide Fuel Cells

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Proton-conducting solid oxide fuel cells (H-SOFCs) are a key technology for energy conversion and storage.
• Developing efficient cathode materials is crucial for optimizing H-SOFC performance.

Purpose of the Study:

• To develop a novel cathode material for H-SOFCs with enhanced chemical compatibility and catalytic activity.
• To investigate the electrochemical performance and underlying mechanisms of nickel-doped barium ferrate cathodes.

Main Methods:

• Synthesis and characterization of nickel-doped barium ferrate (BaCe₀.₂₆Ni₀.₁Fe₀.₆₄O₃-δ, BCNF10) as a composite cathode.
• Electrochemical performance testing of H-SOFCs utilizing the BCNF10 cathode at intermediate temperatures.
• Hydrogen permeation experiments to confirm proton conductivity.
• Density functional theory (DFT) calculations to elucidate the role of nickel doping.

Main Results:

• The optimized BCNF10 composite cathode achieved an outstanding cell performance of 1.04 W cm⁻² at 600 °C.
• The cathode exhibited significant proton conductivity, confirmed by hydrogen permeation experiments.
• DFT calculations revealed that nickel doping enhances hydration formation and proton migration.

Conclusions:

• Nickel-doped barium ferrate demonstrates excellent electrocatalytic activity and proton conductivity, making it a promising cathode material for H-SOFCs.
• The enhanced performance is attributed to improved proton transport facilitated by nickel doping.
• This research contributes to the advancement of efficient energy conversion and storage technologies using H-SOFCs.