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Understanding the mechanism of the interfacial reaction between the cathode material and the electrolyte is a significant work because the interfacial reaction is an important factor affecting the stability, capacity, and cycling performance of Li-ion batteries. In this work, spin-polarized density functional theory calculations with on-site Coulomb energy have been employed to study the adsorption of electrolyte components propylene carbonate (PC) on the LiMn2O4 (100) surface. The findings show that the PC molecule prefers to interact with the Mn atom on the LiMn2O4 (100) surface via the carbonyl oxygen (Oc), with the adsorption energy of −1.16 eV, which is an exothermic reaction. As the adsorption of organic molecule PC increases the Mn atoms coordination with O atoms on the (100) surface, the Mn3 + ions on the surface lose charge and the reactivity is substantially decreased, which improves the stability of the surface and benefits the cycling performance. [ABSTRACT FROM AUTHOR]

The thermodynamics of phosphorus (P) doping to spinel Co3O4, for both bulk cases and (100) and (110) surface cases, is studied using first principles calculations. The doping energies of the P atom at different doping sites are carefully calculated and compared. It is shown that P doping at Co sites, at either tetrahedral or octahedral sites, is energetically favorable, while P doping and replacing O atoms are energetically unfavorable. The doping energy difference is large enough to conclude that P doping has a very strong preference to take the Co sites, rather than the O sites in spinel Co3O4. Even when O-vacancy is available, P doping and taking the O-vacancy site is thermodynamically unfavorable. The physical/chemical mechanism behind this phenomenon is carefully analyzed. Electronic structure analysis shows that P doping and replacing the Co atom brings excess electrons to the Co3O4 system, which is beneficial to enhance the electrochemical and catalytic performance of the spinel Co3O4. Our results clarified the misleading results of P doping and replacing O atoms in spinel Co3O4 reported in the literature. [ABSTRACT FROM AUTHOR]

A first-principles calculation was performed to investigate the switchable CO2 capture on χ3-borophene by injecting/removing the extra electrons. The results show that the CO2 adsorption energy on the neutral χ3-borophene is 0.150 eV. After extra 2.5 e are injected, the adsorption energy is raised up to 0.802 eV, showing a significant enhancement with the change from the physical adsorption to chemical adsorption. Furthermore, both the CO2 capture and release processes are exothermic reactions involving injecting/removing extra electrons. χ3-borophene possesses a metallic electronic structure, which is conducive to the injection of extra electrons. The minimum charge density for CO2 capture on the negatively charged χ3-borophene is 1.6 × 1014 e cm−2. The CO2 capture capacity of χ3-borophene is 4.09 × 1014 cm−2. Finally, we study the selectivity of negatively charged χ3-borophene. The results show that the negatively-charged χ3-borophene possesses a high selectivity for CO2 from its mixtures with CO, CH4, NH3, N2, H2S, and H2. χ3-borophene is a new promising charge-modulated switchable CO2 capture material with good stability, high CO2 capture capacity, high selectivity, and excellent electrical conductivity. [ABSTRACT FROM AUTHOR]

A first-principles calculation was performed to investigate the switchable CO2 capture on χ3-borophene by injecting/removing the extra electrons. The results show that the CO2 adsorption energy on the neutral χ3-borophene is 0.150 eV. After extra 2.5 e are injected, the adsorption energy is raised up to 0.802 eV, showing a significant enhancement with the change from the physical adsorption to chemical adsorption. Furthermore, both the CO2 capture and release processes are exothermic reactions involving injecting/removing extra electrons. χ3-borophene possesses a metallic electronic structure, which is conducive to the injection of extra electrons. The minimum charge density for CO2 capture on the negatively charged χ3-borophene is 1.6 × 1014 e cm-2. The CO2 capture capacity of χ3-borophene is 4.09 × 1014 cm-2. Finally, we study the selectivity of negatively charged χ3-borophene. The results show that the negatively-charged χ3-borophene possesses a high selectivity for CO2 from its mixtures with CO, CH4, NH3, N2, H2S, and H2. χ3-borophene is a new promising charge-modulated switchable CO2 capture material with good stability, high CO2 capture capacity, high selectivity, and excellent electrical conductivity.

Searching for electrode materials for non-lithium metal ion batteries (NLMIBs) is key to the success of NLMIBs. In this work, we investigated the scientific feasibility of using g-Mg 3 N 2 , which is a novel 2D graphene-like material, as an anode for non-lithium metal-ions (Na, K, Mg, Ca and Al) batteries based on density functional theory calculations. The sequential adsorption energy, Bader charge, intercalation voltage, energy-storage capacity, electronic conductivity and metal-ion diffusion energy barrier are calculated. Results show that the metal-ion intercalation potentials and diffusion energy barriers are suitable for battery application. The maximum specific capacities for Na-, K-, Mg-, Ca- and Al-ion on g-Mg 3 N 2 are predicted to be 797, 797, 531, 1594 and 797 mA h g -1 , respectively. The excellent structural stability of g-Mg 3 N 2 is good for the cycling performance. Moreover, the electronic structure of the g-Mg 3 N 2 changes from semiconductor to metal upon metal-ion adsorption, as well as relatively low metal-ion diffusion energy barriers (except for Al-ion diffusion), are beneficial to the charge/discharge rate of the g-Mg 3 N 2 anode., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

It was reported by Hu et al (2015 ACS Appl. Mater. Interfaces 7 24016) that Li adsorption on the Ca 2 N monolayer is energetically unfavorable, although it was found to be a good candidate for Na storage. In this paper, from first-principles calculations, it is shown that compressive stain can greatly enhance the interactions between Li adsorbate and the Ca 2 N host, which is beneficial to prevent Li from clustering on the surface and thus Li storage becomes possible. Charge distribution analysis further shows that the enhanced Li-adsorption is a result of the increased surface charge density and the more confined charge distribution under compressive strain. Inspired by this observation, several electron-donor-doped Ca 2 N materials are considered as anode materials for Li-ion batteries. Results show that the O and F doped Ca 2 N have the best performance, with predicted Li storage capacity reaching about 567.9 and 565.9 mAh g -1 for O and F doped cases, respectively. It is also demonstrated that electron-donor doping does not change the metallic electronic structures and the low Li-ion migration energy barriers on the surface of the Ca 2 N monolayer, and thus the rate performance of the doped Ca 2 N can be as good as the undoped case. Our study offers a deep understanding of the Li interactions with 2D materials and provides an approach of material modification to 2D electrides for battery applications.

The title compound, C32H28N4O2S, crystallizes as a racemate. In the mol-ecule, the bond-angle sum at the C atom of the sulfanyl-idene entity bound to the triazole ring is 360°, with an annular N-C-N bond angle of 102.6 (2)° and two larger N-C-S angles of 127.3 (2) and 130.1 (2)°. The essentially planar 1,2,4-triazole ring (r.m.s. deviation = 0.013 Å) is nearly perpendicular to the phenylpropanone and methoxyphenyl rings , making dihedral angles of 76.9 (2) and 85.2 (2)°, respectively and subtends dihedral angles of 17.6 (2) and 40.3 (2)° with the tolyl and benzylideneamino rings, respectively. There is no π-π stacking between the mol-ecules. The crystal packing is dominated by weak C-H⋯O and C-H⋯N inter-actions, leading to a three-dimensional network structure. An intra-molecular C-H⋯S inter-action also occurs.