Four-Nitrogen Coordinated Transition-Metal Embedded Graphene as Novel Anode Material for Li-Ion Batteries

Developing high-performance energy storage materials is crucial to alleviate the energy crisis. Recently, newly experimentally synthesized graphene derivatives, four-nitrogen coordinated transition-metal embedded graphene (TMN4-G), have attracted considerable attention as sensitive material and active catalysts due to their amazing superlative properties. However, the potential application of TMN4-G as the electrode material for Li-ion batteries (LIBs) has not been reported. In this work, the mechanism of Li-ion adsorption and diffusion on MnN4-G, CoN4-G and NiN4-G was systemically investigated by density functional theory (DFT). The results show that MnN4-G, CoN4-G and NiN4-G possess better thermally stable and higher conductivity. TMN4 embedded graphene is beneficial to enhance the adsorption ability due to the presence of nitrogen and transition-metal atoms. In additionally, interaction region indicator further confirms that this adsorption phenomenon is electrostatic interaction, demonstrating excellent reversibility of the charge/discharge process. Impressively, MnN4-G exhibits lower barrier of 0.31 eV and higher cell voltage of 2.49 V, reflecting its rapid charge–discharge rate. All these characteristics illustrate that MnN4-G is promising anode material for LIBs