Anchoring nanoarchitectonics of 1T’-MoS2 nanoflakes on holey graphene sheets for lithium-ion batteries with outstanding high-rate performance

Interlayer and Phase Engineering Modifications of K-MoS2 @C Nanoflowers for High-Performance Degradable Zn-Ion Batteries

2D transition metal dichalcogenides (TMDs) have garnered significant interest as cathode materials for aqueous zinc-ion batteries (AZIBs) due to their open transport channels and abundant Zn2+ intercalation sites. However, unmodified TMDs exhibit low electrochemical activity and poor kinetics owing to the high binding energy and large hydration radius of divalent Zn2+ . To overcome these limitations, an interlayer engineering strategy is proposed where K+ is preintercalated into K-MoS2 nanosheets, which then undergo in situ growth on carbon nanospheres (denoted as K-MoS2 @C nanoflowers). This strategy stimulates in-plane redox-active sites, expands the interlayer spacing (from 6.16 to 9.42 Å), and induces the formation of abundant MoS2 1T-phase. The K-MoS2 @C cathode demonstrates excellent redox activity and fast kinetics, attributed to the potassium ions acting as a structural "stabilizer" and an electrostatic interaction "shield," accelerating charge transfer, promoting Zn2+ diffusion, and ensuring structural stability. Meanwhile, the carbon nanospheres serve as a 3D conductive network for Zn2+ and enhance the cathode's hydrophilicity. More significantly, the outstanding electrochemical performance of K-MoS2 @C, along with its superior biocompatibility and degradability of its related components, can enable an implantable energy supply, providing novel opportunities for the application of transient electronics.

A 3D Multilevel Heterostructure Containing 2D Vertically Aligned MoS2 Nanosheets and 1D Sandwich C-MoS2-C Nanotubes to Enhance the Storage of Li+ Ions

To overcome the disadvantages of the MoS₂ anode for LIBs in terms of low intrinsic conductivity, poor mechanical stability, and adverse reaction with electrolytes, a 3D multilevel heterostructure (VANS-MoS₂-CNTs) has been successfully prepared by a simple hydrothermal method followed by thermal treatment. VANS-MoS₂-CNTs are made up of 2D vertically aligned MoS₂ nanosheets (VANS) and 1D sandwich C-MoS₂-C nanotubes (CNTs). The sandwich-like nanotube is the core part, which is made up of the MoS₂ nanotube covered by carbon layers on both side surfaces. Due to the special heterostructure, VANS-MoS₂-CNTs have good conductivity, high structured stability, and excellent Li⁺/electron transport, resulting in high discharge capacity (1587 mAh/g at a current density of 0.1 A/g), excellent rate capacity (1330 and 730 mAh/g at current densities of 0.1 and 2 A/g, respectively), and good cyclic stability (1270 mAh/g at 0.1 A/g after 100 cycles).