As a representative type of self-supported templates,cyano-bridged cyanogels provide ideal plateaus for synthesis of three-dimensional (3D) nanostructures.Herein,3D pomegranate-like Fe-doped NiCo nanoassemblies (3D PG-NiCoFe NAs) were synthesized via facile one-step bi-component cyanogel reduction with NaBH4 as the reducing agent.Specifically,the influence of the incorporated Fe amount was carefully investigated by finely adjusting the feeding molar ratios of the Ni/Co/Fe atoms in the precursors.By virtue of the unique structure and enriched oxygen vacancies originated from well-modulated electronic structures,the 3D PG-NiCoFe-211 NAs exhibited outstanding electrocatalytic performances for oxygen evolution reaction (OER) in alkaline solution,outperforming commercial RuO2 catalyst.The current incorporation of foreign metal atom into host material provides some valuable insights into design and synthesis of metal-based nanocatalysts for constructing practical water splitting devices.