Metal–Organic Framework Hybrid‐Assisted Formation of Co3O4/Co‐Fe Oxide Double‐Shelled Nanoboxes for Enhanced Oxygen Evolution

Abstract Rational design of complex metal–organic framework (MOF) hybrid precursors offers a great opportunity to construct various functional nanostructures. Here, a novel MOF‐hybrid‐assisted strategy to synthesize Co 3 O 4 /Co‐Fe oxide double‐shelled nanoboxes is reported. In the first step, zeolitic imidazolate framework‐67 (ZIF‐67, a Co‐based MOF)/Co‐Fe Prussian blue analogue (PBA) yolk–shell nanocubes are formed via a facile anion‐exchange reaction between ZIF‐67 nanocube precursors and [Fe(CN) 6 ] 3− ions at room temperature. Subsequently, an annealing treatment is applied to prepare Co 3 O 4 /Co‐Fe oxide double‐shelled nanoboxes. Owing to the structural and compositional benefits, the as‐derived Co 3 O 4 /Co‐Fe oxide double‐shelled nanoboxes exhibit enhanced electrocatalytic performance for oxygen evolution reaction in alkaline solution.