When developing high performance lithium-ion batteries,high capacity is one of the key indicators.In the last decade,the progress of two-dimensional(2 D) materials has provided new opportunities for boosting the stora...When developing high performance lithium-ion batteries,high capacity is one of the key indicators.In the last decade,the progress of two-dimensional(2 D) materials has provided new opportunities for boosting the storage capacity.Here,based on first-principles calculation method,we predict that MnN monolayer,a recently proposed 2 D nodal-loop halfmetal containing the metallic element Mn,can be used as a super high-capacity lithium-ion batteries anode.Its theoretical capacity is above 1554 mA-h/g,more than four times that of graphite.Meanwhile,it also satisfies other requirements for a good anode material.Specifically,we demonstrate that MnN is mechanically,dynamically,and thermodynamically stable.The configurations before and after lithium adsorption exhibit good electrical conductivity.The study of Li diffusion on its surface reveals a very low diffusion barrier(~ 0.12 eV),indicating excellent rate performance.The calculated average open-circuit voltage of the corresponding half-cell at full charge is also very low(~0.22 V),which facilitates higher operating voltage.In addition,the lattice changes of the material during lithium intercalation are very small(~ 1.2%-~4.8%),which implies good cycling performance.These results suggest that 2 D MnN can be a very promising anode material for lithium-ion batteries.展开更多
基金Project supported by the Scientific Research Fund of Jiangxi Provincial Education Department,China(Grant No.GJJ190962)the National Natural Science Foundation of China(Grant Nos.11904153,51962010,61961027,12064026,and 12064014)Jiangxi Province Natural Science Foundation,China(Grant No.20202BABL211008)。
文摘When developing high performance lithium-ion batteries,high capacity is one of the key indicators.In the last decade,the progress of two-dimensional(2 D) materials has provided new opportunities for boosting the storage capacity.Here,based on first-principles calculation method,we predict that MnN monolayer,a recently proposed 2 D nodal-loop halfmetal containing the metallic element Mn,can be used as a super high-capacity lithium-ion batteries anode.Its theoretical capacity is above 1554 mA-h/g,more than four times that of graphite.Meanwhile,it also satisfies other requirements for a good anode material.Specifically,we demonstrate that MnN is mechanically,dynamically,and thermodynamically stable.The configurations before and after lithium adsorption exhibit good electrical conductivity.The study of Li diffusion on its surface reveals a very low diffusion barrier(~ 0.12 eV),indicating excellent rate performance.The calculated average open-circuit voltage of the corresponding half-cell at full charge is also very low(~0.22 V),which facilitates higher operating voltage.In addition,the lattice changes of the material during lithium intercalation are very small(~ 1.2%-~4.8%),which implies good cycling performance.These results suggest that 2 D MnN can be a very promising anode material for lithium-ion batteries.