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Abstract Incorporating molecular nanolayers (MNLs) at inorganic interfaces offers promise for reaping unusual enhancements in fracture energy, thermal and electrical transport. Here, we reveal that multilayering MNL-bonded inorganic interfaces can result in viscoelastic damping bandgaps. Molecular dynamics simulations of Au/octanedithiol MNL/Au multilayers reveal high-damping-loss frequency bands at 33 ≤ ν ≤ 77 GHz and 278 ≤ ν ≤ 833 GHz separated by a low-loss bandgap 77 ≤ ν ≤ 278 GHz region. The viscoelastic bandgap scales with the Au/MNL interface bonding strength and density, and MNL coverage. These results and the analyses of interfacial vibrations indicate that the viscoelastic bandgap is an interface effect that cannot be explained by weighted averages of bulk responses. These findings prognosticate a variety of possibilities for accessing and tuning novel dynamic mechanical responses in materials systems and devices with significant inorganic–organic interface fractions for many applications, e.g., smart composites and sensors with self-healing/-destructing mechanical responses. 

Abstract Graphite anodes offer low volumetric capacity in lithium‐ion batteries. By contrast, tellurene is expected to alloy with alkali metals with high volumetric capacity (≈2620 mAh cm⁻³), but to date there is no detailed study on its alloying behavior. In this work, the alloying response of a range of alkali metals (A = Li, Na, or K) with few‐layer Te is investigated. In situ transmission electron microscopy and density functional theory both indicate that Te alloys with alkali metals forming A₂Te. However, the crystalline order of alloyed products varies significantly from single‐crystal (for Li₂Te) to polycrystalline (for Na₂Te and K₂Te). Typical alloying materials lose their crystallinity when reacted with Li—the ability of Te to retain its crystallinity is therefore surprising. Simulations reveal that compared to Na or K, the migration of Li is highly “isotropic” in Te, enabling its crystallinity to be preserved. Such isotropic Li transport is made possible by Te's peculiar structure comprising chiral‐chains bound by van der Waals forces. While alloying with Na and K show poor performance, with Li, Te exhibits a stable volumetric capacity of ≈700 mAh cm⁻³, which is about twice the practical capacity of commercial graphite.