Improved Electrochemical Performance of a Li_1.2Ni_0.2Mn_0.6O₂ Cathode by a Hydrothermal Method with a Metal–Organic Framework as a Precursor

Metal–organic frameworks (MOFs) have been successfully applied as precursors and adsorbents to synthesize a Li1.2Ni0.2Mn0.6O2 cathode material via a hydrothermal method. A MOF precursor is composed of Ni2+, Mn2+, and 1,3,5-benzenetricarboxylic acid (BTC) as organic ligands. The prepared Li1.2Ni0.2Mn0.6O2 (M-LLO) has been investigated by X-ray diffraction, scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. Li1.2Ni0.2Mn0.6O2 synthesized by a normal hydrothermal method is prepared for comparison. M-LLO has a purer crystalline phase, higher specific surface area, preferred (100) crystal plane, and Li2CO3 in situ coated layer. These have improved the electrochemical performance of the Li1.2Ni0.2Mn0.6O2 material as a lithium-ion battery (LIB) cathode (98.1% capacity retention after 100 cycles at 1C, 127.6 mAh g–1 at a rate of 5C).