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The solid electrolyte interphase (SEI) is a thin heterogeneous layer formed at the anode/electrolyte interface in lithium‐ion batteries as a consequence of the reduction of the electrolyte. The initial formation of the SEI inhibits the direct contact between the electrode and the electrolyte and thus protects the battery. However, the composition, structure, and size of the SEI evolve over time and the growth of the SEI is considered the primary mechanism leading to the gradual deterioration of the battery performance. Despite the importance of the SEI and its growth, the atomistic understanding of the underlying elementary reaction steps remains partial. Molecular modeling of the electrolyte decomposition is key to gain detailed insights that are complementary to experiments for the reactions occurring in this heterogenous interphase. In this perspective, the electron transport mechanisms are first described from the anode to the electrolyte through the SEI and highlight the importance of the inorganic/organic interface within the heterogeneous SEI: it is where the electrolyte decomposition reactions are likely to occur. Finally, a view is provided on the current progress on molecular modeling techniques (e.g., Density Functional Theory, force fields, machine learning potentials) of the SEI and the challenges each method faces. [ABSTRACT FROM AUTHOR]

Highlights: [•] DFT shows how the environment of the active sites can tune the catalytic reactivity. [•] Alloying Pt with Sn (or Pd with Au) weakens butene adsorption and increases selectivity for butadiene partial hydrogenation. [•] On PtSn, the non-selective pathway for butadiene hydrogenation through a metallacycle intermediate is disadvantaged. [•] For alcohol dehydrogenation, co-adsorbed water plays a key role in assisting OH bond breaking. [Copyright &y& Elsevier]

Abstract: We have performed a detailed study of the cyclization of carbonyl groups on unactivated alkynyl-quinolines. Two cyclization modes are accessible: the exo vs. endo mode. The influence of the substituents of the alkynyl-quinolines have been studied using two examples giving different reactivity: the phenyl and the CH2OMe substituent. From an experimental point of view, the reaction occurs in basic medium and the first step of the reaction has been shown to be the formation of the hemi-acetal. Two mechanisms have been investigated with and without deprotonation of the hemi-acetal prior to the carbon–oxygen bond formation and the proton’s transfer. The influence of the solvent effects has been studied using supermolecular and continuum/supermolecular techniques. The mechanism without deprotonation of the hemi-acetal presents high barriers and the inclusion of solvent effects both with the continuum method and the supermolecular approach stresses strongly this tendency especially when phenyl substituents are used. On the other hand, the base mechanism exhibits lower barriers but solvent effects also increase these barriers, which remain quite reasonable around 15kcalmol−1. Whatever the methods used, the exo mode of reaction appears to be the kinetic pathway whereas the endo mode appears to be under thermodynamic control. [Copyright &y& Elsevier]

The efficiency of direct ethanol fuel cells suffers from the partial oxidation of ethanol into acetic acid as opposed to the complete oxidation of this fuel to CO 2 . Herein, we support the quest for a selective catalyst for ethanol electro-oxidation to CO 2 , building on our previous mechanistic hypothesis based on experimental insight and DFT computations. We derive a simple descriptor of the expected selectivity towards full oxidation, Ω, as a function of the adsorption energy of atomic C and O. Three different families of catalyst surfaces are screened using this descriptor: monometallics, bimetallics and conducting metal oxides, totaling to 600 surfaces. In agreement with available experimental data, no single metal surface is more selective for total oxidation than platinum and palladium. While the selected conducting oxides were not predicted to be selective towards splitting the C C bond, structurally-controlled monometallics (such as Pd(100)) or some bimetallics (Pd 3 Ag) are found to be competitive with the most stable facet, (111), of Pd and Pt. Despite this very extensive screening, no very promising catalyst has been identified. This highlights the need to identify catalysts for acetate oxidation or to exploit support effects and electrolyte engineering to profit from the full power of direct ethanol fuel cells. [ABSTRACT FROM AUTHOR]

To improve lubricant formulation, a better understanding of the wettability properties and hence of the interactions between the surface and the lubricant additives is a key parameter. Herein, we use density functional theory calculations to characterize 32 typical head groups, classified into four categories: protic, aprotic, aromatic and phosphorus-containing molecules. By comparing their adsorption energies on γ-alumina, used as a surface model of aluminium sheets, and their solvation energies in a model lubricant base oil, we found that the solvation energy was not a discriminant parameter while the adsorption energy was critical. Phosphates and carboxylic acids are the most strongly adsorbed, and thus more likely to yield to improved wettability properties of the lubricant through film formation. Image 1 • Ab initio modelling unravels the wettability related competition between solvation and adsorption for lubricant additives. • For lubricants in apolar base oils, the solvation is not critical while the adsorption strength discriminates the additives. • A linear correlation is obtained between the dissociative adsorption energy and the pKa of the head group of the additive. • Phosphates and carboxylic acids are the most adsorbed functional groups and should improve the wettability properties. [ABSTRACT FROM AUTHOR]