Two-dimensional MA2Z4, as another system of a two-dimensional material family, can obtain different materials and considerable properties by replacing the elements M, A, and Z. At present, the physical properties and optical response of MA2Z4 materials have been studied, but there is still a lack of research on the application of MA2Z4 as a transistor channel material to investigate its transistor performance. Here, we employ WGe2N4 as a representative to systematically study the bounce-to-transport properties and gate control capability of ML WGe2N4 field effect transistors below 10 nm via ab initio quantum transport calculations. Until the channel length is down to 3.0 nm, the optimized n/p-type doped WGe2N4 metal–oxide–semiconductor field-effect transistors with proper concentrations and underlap structures can satisfy the high-performance requirements of International Technology Roadmap for Semiconductors of 2013 version, by considering the on-current, subthreshold swing, intrinsic delay time, and dynamic power indicator. Therefore, we can estimate that the monolayer WGe2N4 is a competitive alternative for transistor channel materials in the post-silicon era.

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Lithium−sulfur (Li−S) batteries have attracted great enthusiasm in recent years. Nevertheless, the serious shuttle effect of lithium polysulfides (Li 2 S n ), poor conductivity of S and intermediate products, and relatively slow dynamics make its commercial application face severe challenges. Here, functionalized M 2 CT 2 MXenes (M = Ti, Nb, Cr; T = bare, O, F, OH) were used as the sulfur host to build multifunctional cathodes, in which the inhibition of the shuttle effect by the anchoring effect and accelerating discharging/charging kinetics by electrocatalysis were studied via first-principles. The strong anchoring strength of M 2 CO 2 /M 2 CF 2 to Li 2 S n could effectively suppress the shuttle behavior. The anchoring ability of MXenes is a double-edged sword, and moderate anchoring strength should be considered. Compared comprehensively, Nb 2 CO 2 has a better electrocatalysis performance for the sulfur reduction reaction during discharging. It also accelerates the decomposition of Li 2 S and migration of Li + on the cathode which increases charging kinetics. The improvement in kinetics is related to the enhancement of electronic conductivities of Nb 2 CO 2 −Li 2 S n composites. In short, Nb 2 CO 2 -based multifunctional sulfur cathodes effectively suppress the shuttle effect and improve reaction kinetics. This work expands the application of the MXene family, especially providing guidelines for the utilization of Nb-based MXene in energy storage.