Fabrication of 3D graphene/MoS2 spherical heterostructure as anode material in Li-ion battery

Abstract

Three-dimensional (3D) graphene-based nanocomposites have received considerable attention in both fundamental research and industrial applications, as they combine the functionalities of well-controlled nano-architectures and the integrity of bulk materials. Actually, among these materials, spherical structures are attracting more and more attention worldwide due to their excellent performance in various fields such as drug delivery, heterogeneous catalysis, encapsulation of support, and electrode materials for lithium-ion batteries. Herein, a facile route to fabricate a three-dimensional hierarchical graphene/MoS2 nanocomposite is presented. The molecular heterostructure is derived from graphene oxide flakes and precursors of molybdenum ((NH4)2Mo7O4·4H2O) and sulfur (L-cysteine). Spherical morphology (GO/MoS2) is obtained via self-assembly of the precursor. This 3D nanocomposite exhibits MoS2-nanosheets strongly linked to graphene oxide flakes, which renders it particularly suited to exploit the conversion reaction of MoS2 for electrochemical energy storage. When assembled into an electrode in lithium-ion batteries, as-prepared GO/MoS2 electrodes indeed deliver a high initial charge capacity of 783 mA h g−1 at a current density of 100 mA/g and Coulombic efficiency of more than 96% from the second cycle on exceeding the theoretical capacity of the pristine 2D MoS2 and graphene. Overall, the study sheds some light on the design of 3D heterostructure as a promising anode material in Li-ion batteries.

Computational Study of the Enhancement of Graphene Electrodes for Use in Li–Ion Batteries via Forming Superlattices with Transition Metal Dichalcogenides

“…SnS 2 -T has a flat voltage from a = 0 to a = 2, as neither of the a = 1 configurations was more favorable than a combination of the a = 0 and a = 2 structures. Our results for MoS 2 -T with graphene agree with those of the experiment, where a voltage of ≈1.5 V has been seen, as well as irreversible conversion reactions occurring above this voltage . We note that WS 2 , ScS 2 -R, and ScS 2 -T all show a significant drop in their voltages.…”

“…Our results for MoS 2 -T with graphene agree with those of the experiment, where a voltage of ≈1.5 V has been seen, as well as irreversible conversion reactions occurring above this voltage. 61 We note that WS 2 , ScS 2 -R, and ScS 2 -T all show a significant drop in their voltages.…”

“…Constructing superlattices is an attractive approach for tailoring the properties of two-dimensional materials due to the comparative ease with which they can be made (such as via exfoliation) and has been applied to TMDCs. − Given the layered structure of many battery electrodes in use today, such as NMC, NCA, LiCoO 2 , and graphite, superlattices could be made from these to modify their voltages, capacities, thermal stability, and more in order to improve their overall performance. Some TMDC–graphene superlattices have already been investigated as intercalation electrodes, showing promise as anodes, − with MoS 2 –graphene superlattices showing voltages of 1.5 V and conversion reactions to Li 2 S at 2.3 V . Experimental evaluations of the MoS 2 /graphene systems have indicated that such systems offer improvements in terms of diffusion pathways and could be used for dual Li–Mg systems.…”

Monodisperse MoS2/Graphite Composite Anode Materials for Advanced Lithium Ion Batteries

“…In this context, lithium-ion batteries have rapidly developed into a new generation of energy-storage power supplies based on their characteristics of high specific capacity, high cycle life, small size, light weight, no memory effect, and no pollution. The traditional graphite anode material has a low theoretical capacity (theoretical capacity of 372 mAh/g [ 2 , 3 , 4 ]), and it is easy to form lithium dendrites at room temperature and low temperature, resulting in poor cyclic stability, reduced safety, and other problems that can no longer meet the demand for the high energy density and high power density of power batteries [ 5 , 6 , 7 ].…”

Editorial: Advanced micro/nano materials for electrochemical energy conversion and application

“…Two-dimensional (2D) materials and their based materials also have been proposed as promising candidates of electrode materials in lithium-ion battery due to their unique surface area, pore structure, surface morphology, chemical composition and electrical properties. Wenelska et al 2022) prepared a threedimensional (3D) MoS 2 /graphene anode material for lithiumion batteries through a facile and highly reproducible route. In which, the graphene oxide flakes served as the building blocks and the internal cross-linkage of nano-scale spherical MoS 2 sheets and graphene oxide are benefit to prevent their aggregation and ensure structural stability.…”