Cr-doped LiNi0.5Mn1.5O4 derived from bimetallic Ni/Mn metal-organic framework as high-performance cathode for lithium-ion batteries

Metal-organic frameworks (MOFs) have potential applications in the field of electrochemical energy storage due to their unique characteristics, such as structural diversity, tolerability, and chemical homogeneity. LiNi0.5Mn1.5O4 (LNMO) is a great cathode material due to its wide working voltage, high energy density, and excellent rate capability. In this study, bimetallic Ni/Mn-MOFs and Cr-doped Ni/Mn-MOFs have been prepared by solvothermal reaction, which can be used as the precursor for the synthesis of pristine and Cr-doped LNMOs. The results indicate that the MOF-derived LNMO has better electrochemical behavior than the sample obtained from the conventional co-precipitation route. The resulting MOF-derived LNMO exhibits a high specific capacity (SC, 132.4 mAh/g at 0.2C), good rate ability (116.5 mAh/g at 10C), and remarkable long-cycle performance (80.1 % capacity retention for 200 cycles at 4C). More significantly, the full lithium-ion batteries (LIBs) incorporated with the MOF-derived LNMO as a cathode and Li4Ti5O12 (LTO) as an anode exhibit superior energy storage properties. This finding provides an efficient strategy for preparing high-performance LNMO cathode materials.