Facile hydrothermal synthesis of MoB MBene nanosheets for high-performance wide-temperature lithium-ion batteries

MBene, a novel two-dimensional material derived from bulk ternary metal borides (MAB phase), has attracted increasing attention in recent research. However, the strong covalent bonding within MAB phases hinders the synthesis of pure-phase MBene. Herein, two-dimensional molybdenum boride (MoB) MBene nanosheets are successfully synthesized via a mild hydrothermal etching method, featuring high specific surface area, abundant active sites, and excellent metallic conductivity properties that enable fast lithium-ion diffusion and superior structural stability. In-depth electrochemical in-situ and ex-situ characterizations confirm the rapid charge transfer kinetics, stable phase evolution, and reversible redox behavior of MoB MBene. Complementary theoretical calculations further reveal its robust structural stability, outstanding electronic conductivity, and low lithium-ion diffusion barriers. Consequently, the MoB MBene anode delivers a reversible capacity of 511 mAh g −1 after 2500 cycles at 1000 mA g −1 , and maintains capacities of 261 and 753 mAh g −1 after 200 cycles even at −20 °C and 50 °C, respectively. The corresponding LiFePO 4 -based full cell exhibits capacity retention ≈98.5 % (123 mAh g −1 ) after 1000 cycles at 1000 mA g −1 .