Ruddlesden-Popper-Structured (Pr0.9La0.1)2 (Ni0.8Cu0.2)O4+δ: An Effective Oxygen Electrode Material for Proton-Conducting Solid Oxide Electrolysis Cells

Proton-conducting solid oxide electrolysis cells (H-SOECs) have attracted a lot of attention due to their high efficiency, energy-saving ability, and environmental friendliness. The ideal H-SOEC oxygen electrode materials are triple-conducting oxides with mixed proton (H+), oxygen ion (O2-) and electron (e(-)) conductivity. Herein, the triple conductive oxide Pr2NiO4+delta (PNO)-based perovskite (Pr0.9La0.1)(2)(Ni0.8Cu0.2)O4+delta (PLNCu) is chosen as the oxygen electrode of the H-SOEC with impressive electrochemical performance. Its crystal structure, physicochemical property, and cell performance are discussed in detail. The thermal expansion coefficient of the PLNCu sample is 13.78 x 10(-6) K-1, and the electrical conductivity is 258 S cm(-1) at 450 degrees C. Moreover, the polarization resistance of the single cell is as low as 0.056 Omega cm(2), and the current density at 1.3 V can reach 1.61 A cm(-2) at 750 degrees C, which shows good electrochemical performance. A 100 h long-term test also shows that the cell has good performance and structural stability. Therefore, this work highlights a novel oxygen electrode material (Pr0.9La0.1)(2)(Ni0.8Cu0.2)O4+delta for proton-conducting solid oxide electrolysis cells.