Mechanistic insights into the reversible lithium storage in an open porous carbon via metal cluster formation in all solid-state batteries

Porous carbons are promising anode materials for next generation lithium batteries due to their large lithium storage capacities. However, their high voltage slope during lithiation and delithiation as well as capacity fading due to intense formation of solid electrolyte interphase (SEI) limit their gravimetric and volumetric energy densities. Herein we compare a microporous carbide-derived carbon material (MPC) as promising future anode for all solid-state batteries with a commercial high-performance hard carbon anode. The MPC obtains high and reversible lithiation capacities of 1000 mAh g−1carbon in half-cells exhibiting an extended plateau region near 0 V vs. Li/Li+ preferable for full-cell application. The well-defined micro porosity of the MPC with a specific surface area of >1500 m2 g−1 combines well with the argyrodite-type electrolyte (Li6PS5Cl) suppressing extensive SEI formation to deliver high coulombic efficiencies. Preliminary full-cell measurements vs. nickel-rich NMC-cathodes (LiNi0.9Co0.05Mn0.05O2) provide a considerably improved average potential of 3.76 V leading to a projected energy density as high as 449 Wh kg−1 and reversible cycling for more than 60 cycles. 7Li Nuclear Magnetic Resonance spectroscopy was combined with ex-situ Small Angle X-ray Scattering to elucidate the storage mechanism of lithium inside the carbon matrix. The formation of extended quasi-metallic lithium clusters after electrochemical lithiation was revealed

Combining In Situ Techniques XRD, IR, and C 13 NMR and Gas Adsorption Measurements Reveals CO2 Induced Structural Transitions and High CO2 CH4 Selectivity for a Flexible Metal Organic Framework JUK 8

Flexible metal organic frameworks MOFs are promising materials in gas related technologies. Adjusting the material to processes requires understanding of the flexibility mechanism and its influence on the adsorption properties. Herein, we present the mechanistic understanding of CO2 induced pore opening transitions of the water stable MOF JUK 8 [Zn oba pip ]n, oba2 4,4 amp; 8242; oxybis benzenedicarboxylate , pip 4 pyridyl functionalized benzene 1,3 dicarbohydrazide as well as its potential applicability in gas purification. Detailed insights into the global structural transformation and subtle local MOF adsorbate interactions are obtained by three in situ techniques XRD, IR, and 13CO2 NMR . These results are further supported by single crystal X ray diffraction SC XRD analysis of the solvated and guest free phases. High selectivity toward carbon dioxide derived from the single gas adsorption experiments of CO2 195 and 298 K , Ar 84 K , O2 90 K , N2 77 K , and CH4 298 K is confirmed by high pressure coadsorption experiments of the CO2 CH4 75 25 v v mixture at different temperatures 288, 293, and 298 K and in situ NMR studies of the coadsorption of 13CO2 13CH4 50 50 v v; 195

Dynamic Preisach modelling of ferromagnetic laminations under distorted flux excitation

none8BOTTAUSCIO O; CHIAMPI M; DUPRE L; FIORILLO F; LO BUE M; MELKEBEEK J; REPETTO M; VON RAUCH MBottauscio, Oriano; Chiampi, M; Dupre, L; Fiorillo, F; LO BUE, M; Melkebeek, J; Repetto, M; VON RAUCH, M

Adaptive response of a metal organic framework through reversible disorder disorder transitions

The ultrahigh porosity and varied functionalities of porous metal–organic frameworks make them excellent candidates for applications that range widely from gas storage and separation to catalysis and sensing. An interesting feature of some frameworks is the ability to open their pores to a specific guest, enabling highly selective separation. A prerequisite for this is bistability of the host structure, which enables the framework to breathe, that is, to switch between two stability minima in response to its environment. Here we describe a porous framework DUT-8(Ni)—which consists of nickel paddle wheel clusters and carboxylate linkers—that adopts a configurationally degenerate family of disordered states in the presence of specific guests. This disorder originates from the nonlinear linkers arranging the clusters in closed loops of different local symmetries that in turn propagate as complex tilings. Solvent exchange stimulates the formation of distinct disordered frameworks, as demonstrated by high-resolution transmission electron microscopy and diffraction techniques. Guest exchange was shown to stimulate repeatable switching transitions between distinct disorder states

Adaptive Response of a Metal–organic Framework Through Reversible Disorder–disorder Transitions

A highly porous metal-organic framework (DUT-8(Ni), DUT = Dresden University of Technology) is found to adopt a configurationally-degenerate family of disordered states that respond adaptively to specific guest stimuli. This disorder originates from non-linear carboxylate linkers arranging paddlewheels in closed loops of different local symmetries that in turn propagate as tilings of characteristic complex superstructures. Solvent exchange stimulates the formation of distinct disordered superstructures for specific guest molecules. Electron diffraction by desolvated DUT-8(Ni) nanoparticles demonstrates these superstructures to persist on the nanodomain level. Remarkably, guest exchange stimulates reversible and repeatable switching transitions between distinct disorder states. Deuterium NMR spectroscopy and in situ PXRD studies identify the transformation mechanism as an adaptive singular transformation event.<br /