Novel 2D Layered Molybdenum Ditelluride Encapsulated in Few‐Layer Graphene as High‐Performance Anode for Lithium‐Ion Batteries

Molybdenum ditelluride nanosheets encapsulated in few‐layer graphene (MoTe2/FLG) are synthesized by a simple heating method using Te and Mo powder and subsequent ball milling with graphite. The as‐prepared MoTe2/FLG nanocomposites as anode materials for lithium‐ion batteries exhibit excellent electrochemical performance with a highly reversible capacity of 596.5 mAh g−1 at 100 mA g−1, a high rate capability (334.5 mAh g−1 at 2 A g−1), and superior cycling stability (capacity retention of 99.5% over 400 cycles at 0.5 A g−1). Ex situ X‐ray diffraction and transmission electron microscopy are used to explore the lithium storage mechanism of MoTe2. Moreover, the electrochemical performance of a MoTe2/FLG//0.35Li2MnO3·0.65LiMn0.5Ni0.5O2 full cell is investigated, which displays a reversible capacity of 499 mAh g−1 (based on the MoTe2/FLG mass) at 100 mA g−1 and a capacity retention of 78% over 50 cycles, suggesting the promising application of MoTe2/FLG for lithium‐ion storage. First‐principles calculations exhibit that the lowest diffusion barrier (0.18 eV) for lithium ions along pathway III in the MoTe2 layered structure is beneficial for improving the Li intercalation/deintercalation property. Molybdenum ditelluride nanosheets encapsulated in few‐layer graphene are successfully synthesized through a simple heating and ball‐milling method, and they display superior cycling stability (capacity retention of 99.5% over 400 cycles at 0.5 A g−1). Ex situ X‐ray diffraction and transmission electron microscopy are used to explore the conversion mechanism of MoTe2 with Li.