Three-phase-coexisting anode enabling high-performance water splitting in protonic solid oxide electrolysis cells

Abstract

Protonic solid oxide electrolysis cells (P-SOECs) represent a promising technology for efficient and economical green hydrogen production. However, the development of high-performance anodes that simultaneously achieve excellent catalytic activity and mixed ionic–electronic conductivity remains a significant challenge. In this work, high-performance La_0.9Ba_0.1Co_0.7Ni_0.2Ag_0.1O_3−δ (LBCNA) anodes featuring the coexistence of three-phases—rhombohedral ABO₃-type LBCNA, Ruddlesden–Popper type LBCNA, and Ag metal nanoparticles—were successfully constructed. The optimized LBCNA-900 anode exhibits exceptional catalytic activity, with an ultralow area-specific resistance (ASR) of 0.10 Ω·cm² at 600 °C. When applied in P-SOECs, the LBCNA-900 anode demonstrates remarkable performance, achieving a high current density of 1.8 A·cm⁻² at 1.3 V at 600 °C. Beyond its promising application potential, this synergistic strategy provides a novel design principle for developing advanced electrocatalysts, with potential implications for a broad range of energy conversion and storage technologies.

Graphical abstract

Keywords

hydrogen energy / water splitting / protonic solid oxide electrolysis cell (P-SOEC) / anode

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