Synergistically Designed Dual Interfaces to Enhance the Electrochemical Performance of MoO 2 /MoS 2 in Na- and Li-Ion Batteries.

It is indispensable to develop and design high capacity, high rate performance, long cycling life, and low-cost electrodes materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Herein, MoO 2 /MoS 2 /C, with dual heterogeneous interfaces, is designed to induce a built-in electric field, which has been proved by experiments and theoretical calculation can accelerate electrochemical reaction kinetics and generate interfacial interactions to strengthen structural stability. The carbon foam serves as a conductive frame to assist the movement of electrons/ions, as well as forms heterogeneous interfaces with MoO 2 /MoS 2 through CS and CO bonds, maintaining structural integrity and enhancing electronic transport. Thanks to these unique characteristics, the MoO 2 /MoS 2 /C renders a significantly enhanced electrochemical performance (324 mAh g -1 at 1 A g -1 after 1000 cycles for SIB and 500 mAh g -1 at 1 A g -1 after 500 cycles for LIBs). The current work presents a simple, useful and cost-effective route to design high-quality electrodes via interfacial engineering.