Metal-Organic Gel-Derived Fe_x O_y /Nitrogen-Doped Carbon Films for Enhanced Lithium Storage

The development of cost-effective and flexible electrodes is demanding in the field of energy storage. Herein, flexible Fe_x O_y /nitrogen-doped carbon films (Fe_x O_y /NC-MOG) are prepared by facile electrospinning of Fe-based metal-organic gels (MOGs) followed by high-temperature carbonization. This approach allows the even mixing of fragile coordination polymers with polyacrylonitrile into flexible films while reserving the structural characteristics of coordination polymers. After thermal treatment, Fe_x O_y /NC-MOG films possess uniformly distributed Fe_x O_y nanoparticles and larger accessible surface areas than traditional Fe_x O_y -NC films without MOG. Taking advantage of the unique structure, Fe_x O_y /NC-MOG exhibits a superior rate performance (449.8 mA h g^-1 at 5000 mA g^-1 ) and long cycle life (629.3 mA h g^-1 after 500 cycles at 1000 mA g^-1 ) when used as additive-free anodes in lithium-ion batteries.