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

Unveiling the Influences of In Situ Carbon Content on the Structure and Electrochemical Properties of MoS2/C Composites

In this work, a MoS2/C heterostructure was designed and prepared through an in situ composite method. The introduction of carbon during the synthesis process altered the morphology and size of MoS2, resulting in a reduction in the size of the flower-like structures. Further, by varying the carbon content, a series of characterization methods were employed to study the structure and electrochemical lithium storage performance of the composites, revealing the effect of carbon content on the morphology, structure characteristics, and electrochemical performance of MoS2/C composites. The experimental setup included three sample groups: MCS, MCM, and MCL, with glucose additions of 0.24 g, 0.48 g, and 0.96 g, respectively. With increasing carbon content, the size of MoS2 initially decreases, then increases. Among these, the MCM sample exhibits the optimal structure, characterized by smaller MoS2 dimensions with less variation. The electrochemical results showed that MCM exhibited excellent electrochemical lithium storage performance, with reversible specific capacities of 956.8, 767.4, 646.1, and 561.4 mAh/g after 10 cycles at 100, 200, 500, and 1000 mA/g, respectively.

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).