Mo6+ activated multimetal oxygen-evolving catalysts† †Electronic supplementary information (ESI) available: SEM and TEM images, XANES spectra and extra electrochemical test data. See DOI: 10.1039/c6sc04819f Click here for additional data file.

An amorphous multimetal FeCoMo OER catalyst has been successfully synthesized, activated by high-valence Mo6+, evidencing superior performance over benchmarking IrO2.

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