MXene local vulcanization promotes lithium storage kinetics

【Research Background】

       The research of 2D materials containing transition metals has always been the frontier of materials science. MXene is a new type of two-dimensional layered material discovered in recent years that has electrochemical properties comparable to graphene. From the perspective of energy storage, its unique open structure and good electrical conductivity make it a leader in efficient carrier transportation. When used as a lithium-ion battery (LIB) anode, MXene exhibits redox pseudocapacitance by intercalating de-dissolved ions into the interlayer space. It has been suggested that the storage capacity of ions depends largely on the nature of the surface functional groups. The surface of MXene has rich functional groups, which makes it have considerable application potential in energy storage.

【Achievement Introduction】

        Recently,  Professor Bo Wang, Dianlong Wang of Harbin Institute of Technology and Professor Dou Shixue of Wollongong University in Australia published a research paper in the top academic journal Advanced Materials , entitled Interfacial and Electronic Modulation via Localized Sulfurization for Boosting Lithium Storage Kinetics. The article reported a MXene improves the kinetic performance of lithium ions through local vulcanization modification.

【Graphic introduction】

Figure 1. Synthesis process of Fe 3 O 4 / FeS @ S-MX

Figure 2. SEM, TEM, XRD and XPS related tests of materials. It can be seen that Fe 3 O 4 / FeS @ S-MX has a 3D interconnected layered structure and Fe 3 O 4 / FeS nanoparticles are partially vulcanized.

Figure 3. Half-cell electrochemical performance test. It can be seen that the modified material has better long-cycle stability and excellent rate performance.

Figure 4. In-situ characterization and analysis of lithium ion migration path during charge and discharge.

【Summary of this article】

       In this paper, a simple co-precipitation method and vulcanization method are proposed to controlly embed a well-structured Fe 3 O 4 / FeS heterostructure on the surface of MXene . The three-dimensional cross-linked porous structure constructed from conductive MXene nanosheets provides a smooth path for the transfer of electrons and Li + and provides enough space for volume expansion. At the same time, the formation of external FeS can effectively adjust the electronic properties of Fe 3 O 4 , thereby improving the reaction kinetics and structural stability.

Literature link

DOI: 10.1002 / adma.202000151

Source: MXene Frontier