Alternative solid electrolytes are the next key step in advancing lithium batteries with better thermal and chemical stability. A soft solid electrolyte, (Adpn)LiPF (Adpn, adiponitrile), is synthesized and characterized that exhibits high thermal and electrochemical stability and good ionic conductivity, overcoming several limitations of conventional organic and ceramic materials. The surface of the electrolyte possesses a liquid nano-layer of Adpn that links grains for a facile ionic conduction without high pressure/temperature treatments.
View Article and Find Full Text PDFIn this work, the possible mechanisms for the reactions of CO with various positional isomers of methylpiperidines (MPs) (N-MP, 2-MP, 3-MP, and 4-MP) including the effect of aqueous solvation have been explored using quantum chemical methods. The major pathways investigated for CO capture in aqueous amines are carbamate formation, its hydrolysis, and the bicarbonate formation (CO + HO + MP) reaction. The calculations indicate that an axial orientation for the methyl group and an equatorial for the COO group could be energetically ideal in the carbamate product of MPs.
View Article and Find Full Text PDFGlyme-based sodium electrolytes show excellent electrochemical properties and good chemical and thermal stability compared with existing carbonate-based battery electrolytes. In this investigation, we perform classical molecular dynamics (MD) simulations to examine the effect of concentration and temperature on ion-ion interactions and ion-solvent interactions via radial distribution functions (RDFs), mean residence time, ion cluster analysis, diffusion coefficients, and ionic conductivity in sodium hexafluorophosphate (NaPF) salt in diglyme mixtures. The results from MD simulations show the following trends with concentration and temperature: The Na---O(diglyme) interactions increase with concentration and decrease with temperature, while the Na---F(PF) interactions increase with concentration and temperature.
View Article and Find Full Text PDFEnergetic materials (EMs) are central to construction, space exploration, and defense, but over the past 100 years, their capabilities have improved only minimally as they approach the CHNO energetic ceiling, the maximum energy density possible for EMs based on molecular carbon-hydrogen-nitrogen-oxygen compounds. To breach this ceiling, we experimentally explored redox-frustrated hybrid energetic materials (RFH EMs) in which metal atoms covalently connect a strongly reducing fuel ligand (e.g.
View Article and Find Full Text PDFA new type of crystalline solid, termed "solvate sponge crystal", is presented, and the chemical basis of its properties are explained for a melt- and press-castable solid sodium ion conductor. X-ray crystallography and atomistic simulations reveal details of atomic interactions and clustering in (DMF)NaClO and (DMF)NaClO (DMF = '-dimethylformamide). External pressure or heating results in reversible expulsion of liquid DMF from (DMF)NaClO to generate (DMF)NaClO.
View Article and Find Full Text PDFIn this investigation, we examine the effect of water concentration and temperature on the dynamical properties of [Hmim][Cl] and [Hmim][NTf2] ionic liquids (ILs). The dynamical properties such as translational diffusion coefficients, ion-pair lifetimes, and rotational correlation times are calculated using molecular dynamics simulations. The simulations predict that water concentration also significantly impacts the magnitude of dynamical properties.
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