Atomically Resolved Defects on Thin Molybdenum Carbide (α-MoC) Crystals.

Thin transition metal carbides (TMCs) garnered significant attention in recent years due to their attractive combination of mechanical and electrical properties with chemical and thermal stability. On the other hand, a complete picture of how defects affect the physical properties and application potential of this emerging class of materials is lacking. Here, we present an atomic-resolution study of defects on thin crystals of molybdenum carbide (α-MoC) grown via chemical vapor deposition (CVD) by way of conductive atomic force microscopy (C-AFM) measurements under ambient conditions.

Intercalation of argon in honeycomb structures towards promising strategy for rechargeable Li-ion batteries.

High-performance rechargeable batteries are becoming very important for high-end technologies with their ever increasing application areas. Hence, improving the performance of such batteries has become the main bottleneck to transferring high-end technologies to end users. In this study, we propose an argon intercalation strategy to enhance battery performance via engineering the interlayer spacing of honeycomb structures such as graphite, a common electrode material in lithium-ion batteries (LIBs).

First principles assessment of the phase stability and transition mechanisms of designated crystal structures of pristine and Janus transition metal dichalcogenides.

Two-dimensional Transition Metal Dichalcogenides (TMDs) possessing extraordinary physical properties at reduced dimensionality have attracted interest due to their promise in electronic and optical device applications. However, TMD monolayers can show a broad range of different properties depending on their crystal phase; for example, H phases are usually semiconductors, while the T phases are metallic. Thus, controlling phase transitions has become critical for device applications.

Alkali Metal Intercalation in MXene/Graphene Heterostructures: A New Platform for Ion Battery Applications.

The adsorption and diffusion of Na, K, and Ca atoms on MXene/graphene heterostructures of MXene systems ScC(OH), TiCO, and VCO are systematically investigated by using first-principles methods. We found that alkali metal intercalation is energetically favorable and thermally stable for TiCO/graphene and VCO/graphene heterostructures but not for ScC(OH). Diffusion kinetics calculations showed the advantage of MXene/graphene heterostructures over sole MXene systems as the energy barriers are halved for the considered alkali metals.

Determination of Dynamically Stable Electrenes toward Ultrafast Charging Battery Applications.

Electrenes, an atomically thin form of layered electrides, are very recent members of the 2D materials family. In this work, we employed first-principle calculations to determine stable, exfoliatable, and application-promising 2D electrene materials among possible MX compounds, where M is a group II-A metal and X is a nonmetal element (C, N, P, As, and Sb). The promise of stable electrene compounds for battery applications is assessed via their exfoliation energy, adsorption properties, and migration energy barriers toward relevant Li, Na, K, and Ca atoms.