Nickel–iron composites are efficient in catalyzing oxygen evolution. Here, we develop a microorganism corrosion approach to construct nickel–iron hydroxides. The anaerobic sulfate-reducing bacteria, using sulfate as the electron acceptor, play a significant role in the formation of iron sulfide decorated nickel–iron hydroxides, which exhibit excellent electrocatalytic performance for oxygen evolution. Experimental and theoretical investigations suggest that the synergistic effect between oxyhydroxides and sulfide species accounts for the high activity. This microorganism corrosion strategy not only provides efficient candidate electrocatalysts but also bridges traditional corrosion engineering and emerging electrochemical energy technologies.

Oxygen electrocatalysis is of great significance in electrochemical energy conversion and storage. Many strategies have been adopted for developing advanced oxygen electrocatalysts to promote these technologies. In this invited contribution, recent progress in understanding the oxygen electrochemistry from theoretical and experimental aspects is summarized. The major categories of oxygen electrocatalysts, namely, noble‐metal‐based compounds, transition‐metal‐based composites, and nanocarbons, are successively discussed for oxygen reduction and evolution. Design strategies of various oxygen electrocatalysts and their relationship on the structure–activity–performance are comprehensively addressed with the perspectives. Finally, the challenge and outlook for advanced oxygen electrocatalysts are discussed toward energy conversion and storage technologies.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/aenm.201901503. Oxygen EvolutionElectrochemical energy conversion and storage devices including metal-air batteries, regenerative fuel cells, and watersplitting cells are critical to satisfy the future energy demand of human society. Oxygen evolution reaction (OER) is the key reaction in these technologies and accounts for the major performance loss due to its sluggish kinetics. Precious metal-based catalysts are used predominantly, but the scarcity and low stability limit their application at large scale. [1] As a consequence, intensive efforts have been devoted to developing cost-effective catalysts with superior oxygen-evolving activity and stability. [2] Earth-abundant metal chalcogens, pnictogens, and metalloids have emerged as potential materials for water oxidation in