Amorphous Metal–Organic Framework‐Dominated Nanocomposites with Both Compositional and Structural Heterogeneity for Oxygen Evolution

Amorphous metal–organic frameworks ( a MOFs) are an emerging family of attractive materials with great application potential, however a MOFs are usually prepared under harsh conditions and a MOFs with complex compositions and structures are rarely reported. In this work, an a MOF‐dominated nanocomposite ( a MOF‐NC) with both structural and compositional complexity has been synthesized using a facile approach. A ligand‐competition amorphization mechanism is proposed based on experimental and density functional theory calculation results. The a MOF‐NC possesses a core–shell nanorod@nanosheet architecture, including a Fe‐rich Fe‐Co‐ a MOF core and a Co‐rich Fe‐Co‐ a MOF shell in the core–shell structured nanorod, and amorphous Co(OH) 2 nanosheets as the outer layer. Benefiting from the structural and compositional heterogeneity, the a MOF‐NC demonstrates an excellent oxygen evolution reaction activity with a low overpotential of 249 mV at 10.0 mA cm −2 and Tafel slope of 39.5 mV dec −1 .