Synthesis of novel MOF-based ZIF-67 hollow nanospheres for lithium-ion battery anode applications

The limited ion transport and low active site utilization in traditional carbon-based anode materials remain major challenges that restrict the performance of lithium-ion batteries (LIBs). To address this issue, a hollow nanostructured anode material derived from zeolitic imidazolate framework-67 (ZIF-67) was developed, featuring enhanced porosity and heteroatom doping. Hollow ZIF-67 nanospheres were synthesized via a self-sacrificial template strategy and subsequently converted into nitrogen-doped carbon-coated cobalt hollow carbon spheres (N/C@Co HCSs) through high-temperature pyrolysis. This design reduces internal inactive volume, increases the density of accessible active sites, and improves both ion/electron transport. Benefiting from these features, N/C@Co-700 delivers a high reversible capacity of 918 mA h g −1 after 600 cycles at 1 A g −1 . In the rate performance test, it retains 597.2 mA h g −1 at 1 A g −1 and recovers to 829.7 mA h g −1 when the current returns to 0.1 A g −1 , indicating excellent structural stability and electrochemical reversibility. Galvanostatic intermittent titration technique and distribution of relaxation time analyses further confirm a high lithium-ion diffusion coefficient ranging from 10 to 9.5 to 10 –12.03 cm 2 s −1 . Compared with conventional MOF-derived carbons, this system offers superior ion kinetics and cycling stability. Overall, this study not only highlights the potential of ZIF-67-derived hollow nanostructures in advanced LIB anodes, but also provides a versatile structural framework for future applications in energy storage, catalysis, and beyond.