Nano-Engineered Interfaces in Dual-Layer Electrodes for Protonic Ceramic Cells with Enhanced Stability and Kinetics

Area of Science:

• Materials Science
• Electrochemistry
• Chemical Engineering

Background:

• Protonic ceramic cells (PCCs) face challenges in interfacial stability and charge transfer, limiting durability and efficiency.
• Structural degradation and high interfacial resistance are key issues in PCC operation.
• Current solutions often involve corrosive treatments, which are undesirable for practical applications.

Purpose of the Study:

• To develop a nanoengineered dual-layer oxygen electrode architecture for PCCs.
• To enhance interfacial stability, mechanical robustness, and electrochemical kinetics.
• To improve the durability and efficiency of protonic ceramic cells.

Main Methods:

• Fabrication of a hierarchical electrode architecture with a fine-grained nanoparticle interfacial contact layer beneath a porous catalytic backbone.
• Characterization of the interfacial layer's sintering activity, bonding, adhesion, and pathway formation with the BCZYYb electrolyte.
• Electrochemical evaluation including impedance spectroscopy, power density measurements, and electrolysis current density testing.
• Assessment of mechanical properties (peel strength) and long-term stability under various operating conditions.

Main Results:

• The dual-layer architecture achieved a peel strength of 44.53 N/cm², a 40% improvement in peak power density (0.96 W cm⁻² at 600 °C), and a 130% enhancement in electrolysis current density (4.78 A cm⁻² at 1.57 V).
• The design effectively mitigated delamination, redistributed mechanical stress, and established efficient ionic/electronic pathways.
• Electrochemical performance showed reduced interfacial polarization resistance and accelerated electrode kinetics.
• The electrode demonstrated stability across 450-600 °C, resilience to voltage cycling, and suppressed interfacial resistance growth over prolonged use, with 88% Faradaic efficiency under high steam concentrations.

Conclusions:

• Nano-scale interface engineering is a powerful strategy for enhancing both mechanical robustness and electrochemical kinetics in PCCs.
• The developed dual-layer architecture offers a scalable and durable platform for improving solid-state electrochemical systems.
• This approach holds significant promise for advancing reversible fuel cells and hydrogen production technologies.