Unraveling MoS₂ and Transition Metal Dichalcogenides as Functional Zinc-Ion Battery Cathode: A Perspective

The zinc-ion battery (ZIB) is considered as one of the most important alternative battery chemistries to date. However, one of the challenges in ZIB development is the limited selection of materials that can exhibit satisfactory Zn²⁺ storage. Transition metal dichalcogenides (TMDs) are widely investigated in energy-related applications due to their distinct physical and chemical properties. In particular, the wide interlayer spacings for these TMDs are particularly attractive as viable Zn²⁺ storage sites. Despite the suitability of TMDs in ZIB application, they are still not widely explored due to their limited report in this area. In this perspective review, the key challenge of TMDs, especially for MoS₂, in their utilization as ZIB cathode are discussed. The various reports on MoS₂ and TMDs as ZIB cathodes are also summarized. In order to elicit reasonable Zn²⁺ storage ability in MoS₂ and TMDs, four key modification strategies are proposed: 1) interlayer engineering, 2) defect engineering, 3) hybridization, and 4) phase engineering. These proposed modification strategies may be able to address the challenge of inadequate Zn²⁺ storage in MoS₂ and TMDs. Finally, this review ends with a conclusion and outlook of MoS₂ and TMDs in the future development of ZIB cathodes.