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Abstract Superconducting quantum metamaterials are expected to exhibit a variety of novel properties, but have been a major challenge to prepare as a result of the lack of appropriate synthetic routes to high‐quality materials. Here, the discovery of synthesis routes to block copolymer (BCP) self‐assembly‐directed niobium nitrides and carbonitrides is described. The resulting materials exhibit unusual structure retention even at temperatures as high as 1000 °C and resulting critical temperature,T_c, values comparable to their bulk analogues. Applying the concepts of soft matter self‐assembly, it is demonstrated that a series of four different BCP‐directed mesostructured superconductors are accessible from a single triblock terpolymer. Resulting materials display a mesostructure‐dependentT_cwithout substantial variation of the XRD‐measured lattice parameters. Finally, field‐dependent magnetization measurements of a sample with double‐gyroid morphology show abrupt jumps comparable in overall behavior to flux avalanches. Results suggest a fruitful convergence of soft and hard condensed matter science. 

Abstract While lithium ion batteries with electrodes based on intercalation compounds have dominated the portable energy storage market for decades, the energy density of these materials is fundamentally limited. Today, rapidly growing demand for this type of energy storage is driving research into materials that utilize alternative reaction mechanisms to enable higher energy densities. Transition metal compounds are one such class of materials, with storage enabled by “conversion” reactions, where the material is converted to new compound upon lithiation. MoS₂is one example of this type of material that has generated a large amount of interest recently due to its high theoretical lithium storage capacity compared to graphite. Here, cryogenic scanning transmission electron microscopy techniques are used to reveal the atomic‐scale processes that occur during reaction of a model monolayer MoS₂system by enabling the unaltered atomic structure to be determined at various levels of lithiation. It is revealed that monolayer MoS₂can undergo a conversion reaction even with no substrate, and that the resulting particles are smaller than those that form in bulk MoS₂, likely due to the more limited 2D diffusion. Additionally, while bilayer MoS₂undergoes intercalation with a corresponding phase transition before conversion, monolayer MoS₂does not.