Interfacial engineering of Ag nanodots/MoSe2 nanoflakes/Cu(OH)2 hybrid-electrode for lithium-ion battery.

ABSTRACT

Although the Lithium ion batteries (LIBs) have attracted remarkable attentions, their practical development is hindered by the low rate performance and poor unit area capacity, which is significantly caused by the low conductivity of the active electrode materials. Herein, a three-dimensional (3D) architecture consisting of Ag nanodots embedded MoSe2 sheets wrapping Cu(OH)2 nanorods (Cu(OH)2/MoSe2/Ag) hybrids were in-situ synthesized on self-standing Cu- foam collector for LIBs application. The 2D MoSe2 nanoflakes supported on 1D highly conductive Cu nanowires provides efficient pathways for both electrons and ions. The embedded Ag nanodots in the MoSe2 as the internal-plane active sites not only improves the intrinsic conductivity but also allows the reversible formation and decompose of Ag-Li alloy, and thus leading to the promotion of Li+ ion storage. As a result, the Cu(OH)2/MoSe2/Ag electrode exhibits a high reversible discharge capacity of 1285.5 mAh g-1 (current density of 0.2 C), good rate performance (discharge-specific capacity remained 544.8 mAh g-1 at 5.0C), and excellent cycling stability (with almost no decay after 500 cycles). Significantly, the 3D Cu(OH)2/MoSe2/Ag electrode exhibits a high areal capacity of 2.50 mAh cm-2 at a high current density of 1.82 mA cm-2. This work provides the new insight into interfaces engineering for 3D architecture toward advanced self-standing LIB electrodes.