High-performance and excellent thermal cycling stability of reversible protonic ceramic cells enabled by a promising Sr/Co-free PrNi0.5Fe0.5O3−δ air electrode

The suppressed mismatch in thermal expansion coefficient between a thermomechanically durable Sr/Co-free PrNi 0.5 Fe 0.5 O 3− δ air electrode and a typical BaZr 0.4 Ce 0.4 Y 0.1 Yb 0.1 O 3− δ electrolyte leads to significantly enhanced thermal cycling stability.