High‐Entropy Perovskite Nanofibers for Bifunctional Air Electrodes in Reversible Protonic Ceramic Electrochemical Cells (Adv. Funct. Mater. 17/2026)

High-Entropy Perovskite Nanofibers In their Research Article (10.1002/adfm.202517768), Kang Taek Lee and co-workers introduce a high-entropy nanofiber air-electrode architecture that leverages entropically driven lattice modulation to enhance oxygen electrocatalysis and stabilize the perovskite framework under harsh operating environments. By promoting rapid oxygen exchange, facilitating hydroperoxide adsorption, and suppressing steam- and CO2-induced degradation, this design overcomes long-standing durability limitations in PCECs, delivering high power output, efficient electrolysis performance, and exceptional long-term operational stability.