We used pentacarboxylic acid ligand 3, 5-di(2', 4'-dicarboxylphenyl) benzoic acid (H₅L) to synthesize two structural similarity lanthanide-cobalt heteronuclear bimetallic organic frameworks (Ln-Co-MOFs) by hydrothermal method: (C₂H₆NH₂)₅{[Eu₉Co(L)₆(H₂O)₅(OH)₄] ·5DMF}_n (1), (C₂H₆NH₂)₂{[Sm₉Co(L)₆(H₂O)₃Cl] ·5DMF}_n (2). The structures were characterized and the property was tested by single crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry, infrared, fluorescence spectra, and magnetism. The results show that 1 and 2 both belong to the trigonal R3 space group and have novel 3D structures and good thermal stability. Among them, 1 has strong fluorescence properties, which can sensitively identify drug molecules sulfasalazine and organic molecules glutaraldehyde. The detection limits could reach 0.95 and 2.10 μmol·L^-1, respectively. In addition, 1 and 2 were antiferromagnetic at 1 kOe.

P2型层状过渡金属氧化物(P2-Na_xTMO₂)因其优异的循环稳定性和倍率性能，成为钠离子电池正极材料的有力候选者。然而，其在高电压下的不可逆相变和固有低理论容量问题，阻碍了实际应用。本研究工作提出高熵策略与双相结构的协同设计来克服这些挑战。通过在P2相高熵基体中引入O3相，构建新型P2/O3双相高熵层状氧化物Na_0.70Ni_0.25Mn_0.35Co_0.15Fe_0.05Ti_0.20O₂ (简称Na_0.70NMCFT)。其中，高熵设计通过构型熵稳定效应有效抑制P2相的不可逆相变，而O3相则通过协同作用弥补容量不足并提升循环稳定性。此外，双相组分之间的相互作用进一步促进P2-O3与P2-P3相变的高度可逆性。Na_0.70NMCFT在1C倍率下的初始放电容量为102.08 mAh g⁻¹，200次循环后容量保持率达88.15%，表明具有优异的循环稳定性。更重要的是，即使在10C的高倍率下，Na_0.70NMCFT仍能提供85.67 mAh g⁻¹的初始放电比容量，并在1000次循环后容量保持率达70%。本工作证实双相高熵设计在提升钠离子电池正极性能中的关键作用，为开发先进钠离子电池正极材料提供了新思路。