A Stable Bifunctional Catalyst for Rechargeable Zinc–Air Batteries: Iron–Cobalt Nanoparticles Embedded in a Nitrogen‐Doped 3D Carbon Matrix

are demonstrated. An all-solid-state battery had an outstanding lifetime and high cell efficiency even upon bending. In situ X-ray absorption spectroscopy revealed that OOH* and O* intermediates induce variations in the Fe-Fe and Co-Co bond lengths, respectively, suggesting that Fe and Co species are crucial to the ORR/OER processes.