Heterostructures Stimulate Electric-Field to Facilitate Optimal Zn 2+ Intercalation in MoS 2 Cathode.

The electric-field effect is an important factor to enhance the charge diffusion and transfer kinetics of interfacial electrode materials. Herein, by designing a heterojunction, the influence of the electric-field effect on the kinetics of the MoS 2 as cathode materials for aqueous Zn-ion batteries (AZIBs) is deeply investigated. The hybrid heterojunction is developed by hydrothermal growth of MoS 2 nanosheets on robust titanium-based transition metal compound ([titanium nitride, TiN] and [titanium oxide, TiO 2 ]) nanowires, denoted TNC@MoS 2 and TOC@MoS 2 NWS, respectively. Benefiting from the heterostructure architecture and electric-field effect, the TNC@MoS 2 electrodes exhibit an impressive rate performance of 200 mAh g -1 at 50 mA g -1 and cycling stability over 3000 cycles. Theoretical studies reveal that the hybrid architecture exhibits a large-scale electric-field effect at the interface between TiN and MoS 2 , enhances the adsorption energy of Zn-ions, and increases their charge transfer, which leads to accelerated diffusion kinetics. In addition, the electric-field effect can also be effectively applied to TiO 2 and MoS 2 , confirming that the concept of heterostructures stimulating electric-field can provide a relevant understanding for the architecture of other cathode materials for AZIBs and beyond.