Storage of Lithium-Ion by Phase Engineered MoO Homojunctions.

With high theoretical specific capacity, the low-cost MoO is known to be a promising anode for lithium-ion batteries. However, low electronic conductivity and sluggish reaction kinetics have limited its ability for lithium ion storage. To improve this, the phase engineering approach is used to fabricate orthorhombic/monoclinic MoO (α/h-MoO) homojunctions. The α/h-MoO is found to have excessive hetero-phase interface. This not only creates more active sites in the MoO for Li storage, it regulates local coordination environment and electronic structure, thus inducing a built-in electric field for boosting electron/ion transport. In using α/h-MoO, higher capacity (1094 mAh g at 0.1 A g) and rate performance (406 mAh g at 5.0 A g) are obtained than when using only the single phase h-MoO or α-MoO. This work provides an option to use α/h-MoO hetero-phase homojunction in LIBs.