| 초록 |
The tunnel-type Na0.44MnO2 as promising cathode materials for sodium-ion batteries (SIBs) have attracted interest owing to its abundant resources and potential low cost. However, manganese disproportionation associated with Mn3+ is hindering their practical application, resulting in rapid capacity decay and poor rate capability. Herein, a Li-substituted, tunnel/spinel heterostructured cathode is successfully synthesized to overcome these limitations. The multiphase transformation was prohibited by the Li dopant, which improves the structural reversibility. Meanwhile, the tunnel/spinel heterostructure provides 3D Na+ diffusion channels to effectively enhance the redox reaction kinetics. The optimized [Na0.396Li0.044][Mn0.97Li0.03]O2 composite delivers an excellent rate performance and cycle performance, demonstrating the potential of the cathode for practical applications. This strategy could be milestone for further sodium-deficient cathode materials. |
