Subsequent dehydration of N -maleanilic acid 3 using acetic anhydride furnished the unexpected isomaleimide 5-((4-((4-bromophenyl)selanyl)phenyl)imino)furan-2(5H)-one ( 4 ) instead of the maleimide 5.
N -Maleanilic acid 3 was obtained in 94% yield via the reaction of selenoamine 2 with toxilic anhydride. Reduction of 4,4′-diselanediyldianiline ( 1 ) followed by the reaction with bromo-4-(bromomethyl)benzene afforded the corresponding 4-((4-bromobenzyl)selanyl)aniline ( 2 ) in 85% yield. The general theory of cation-disorder formation may also find applications in electrochemical water treatment and ion separations, such as lithium extraction from brines, based on competitive ion intercalation in battery materials. The theory provides a framework to guide the development of cathode compositions, coatings and electrolytes to enhance rate capability and enhance battery lifetime.
The model is used in battery cycling simulations to describe the extent of cathode degradation when using different voltage cutoffs, in agreement with experimental observations that lower-voltage cycling can substantially reduce cathode degradation. In the case of nickel-rich oxides, we hypothesize that nickel with a high concentration of defects is driven into the bulk by electrostatic forces as oxidation reactions at the solid-electrolyte interface remove oxygen ions at high potentials (>4.4V vs. The model accounts for defect core energies, long-range dipolar electrostatic forces, and configurational entropy of the solid solution.
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We develop a general free energy model for layered-oxide ion-intercalation materials as a function of the degree of disorder, which represents the density of defects in the host crystal. Disorder-driven degradation phenomena, such as structural phase transformations and surface reconstructions, can significantly reduce the lifetime of Li-ion batteries, especially those with nickel-rich layered-oxide cathodes.