Bifunctional bimetallic zeolitic imidazolate frameworks with a nanoflower structure for sodium-ion storage and...

Although zeolitic imidazolate frameworks (ZIFs) are widely applied in the energy storage and catalysis fields, their multifunctional applications are extremely limited by their closed rhombohedral dodecahedron structure. Herein, a bimetallic CoFe-ZIF with an open nanoflower structure is synthesized via a simple one-step stirring strategy at room temperature. CoFe-ZIF exhibits superior sodium-ion storage performance as the anode for sodium-ion batteries (SIBs) and glucose sensing performance as the electrode for a non-enzymatic glucose sensor, as a result of the synergistic effect between the metal ions and highly open nanoflower structure. CoFe-ZIF exhibits a specific capacity of 410.32 mA h g^-1 at a current density of 0.10 A g^-1 after 500 cycles for SIBs and a high sensitivity of 1484.22 μA mM^-1 cm^-2 in the range of 0.30-2.00 mM for glucose sensing, which also shows a low detection limit of less than 25 μM. This work also provides insight into designing bimetallic MOFs via a simple strategy for multifunctional device applications.