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Ammonia is an indispensable commodity and a potential carbon free energy carrier. The use of H permeable electrodes to synthesize ammonia from N2, water and electricity, provides a promising alternative to the fossil fuel based Haber‐Bosch process. Here, H permeable Ni electrodes are investigated in the operating temperature range 25–120 °C, and varying the rate of electrochemical atomic hydrogen permeation. At 120 °C, a steady reaction is achieved for over 12 h with 10 times higher cumulative NH3 production and almost 40‐fold increase in faradaic efficiency compared to room temperature experiments. NH3 is formed with a cell potential of 1.4 V, corresponding to a minimum electrical energy investment of 6.6 kWh kg−1NH3 ${{_{{\rm NH}{_{3}}}}}$. The stable operation is attributed to a balanced control over the population of N, NHx and H species at the catalyst surface. These findings extend the understanding on the mechanisms involved in the nitrogen reduction reaction and may facilitate the development of an efficient green ammonia synthesis process. [ABSTRACT FROM AUTHOR]

Nanostructured solid composite electrolyte or nano‐SCE, which is composed of an ionic liquid, nanoporous silica, and residuals of immobilized precursor components, shows promising synergistic properties. The ionic conductivity of nano‐SCE is in the range of 2–5 mS cm−1, which exceeds the bulk ionic liquid conductivity at ambient temperature, while maintaining characteristics of a solid electrolyte such as having no leakage issues as the ionic liquid is confined, and lower flammability compared to conventional liquid electrolytes. In this study, the underlying mechanism of enhanced conductivity is investigated by using magic angle spinning NMR and NMR relaxometry analysis. Water, one of the volatile precursor molecules has shown to play a key role in the final conductivity and stability at the solid‐electrolyte interface, as it enhances the temperature range in which the ionic liquid remains mobile. In line with previous studies, water with lowered mobility is found in the silicon matrix. The activation energies of lithium ion transfer probed by NMR relaxometry, however, do not change as function of water content. The increase in bulk mobility of lithium ions under ambient conditions compared to water‐less nano‐SCE is found to be the origin of the altered conductivity of this material. [ABSTRACT FROM AUTHOR]

The lithiated anatase of Ti[O.sub.2] is analyzed and studied by increasing the Li capacity and solubility for decreasing particle size to describe the particle size dependence of insertion reactions, which are highly important for various energy storage devices. The analysis shows that the particle size induces a solid solution behavior in the complexes, which can be further used fundamentally for several other two-phase lithium or hydrogen insertion reactions.

A detailed structural data is obtained for LixMg(sub 0.1)Ni(sub 0.4)Mn(sub 1.5)O(sub 4) spinels, intercalated with lithium in the range 1less than equal to x less than equal 2.25, by simultaneous reitveld refinement of X-ray and neutron diffraction data. Extensive migration of Ni and Mn duringlithium insertion is found, resulting in the disappearance of the initial Ni-Mn ordering and the formation of Ni-rich and Ni-poor domains.

The dynamics of the polyaromatic cores are of vital importance as they help in examining the electrical conductivities of the columns. It is found that the dynamics of the inner core and the alkyl tails of discotics are strongly correlated.

The (super 7)Li magic angle spinning solid-state nuclear magnetic resonance is applied to examine the lithium local environment and lithium ion mobility in tetragonal anatase TiO2 and orthorhombic lithium titanate Li(sub 0.6)TiO2. The chemical shifts of lithium in anatase and in lithium titanate are independent of temperature up to about 250 K and decrease at higher temperatures, indicating a change in mainly the 3d conduction electron density.

Discotic liquid crystalline (DLC) charge transfer (CT) complexes combine visible light absorption and rapid charge transfer characteristics, being favorable properties for photovoltaic (PV) applications. We present a detailed study of the electronic and vibrational properties of the prototypic 1:1 mixture of discotic 2,3,6,7,10,11-hexakishexyloxytriphenylene (HAT6) and 2,4,7-trinitro- 9-fluorenone (TNF). It is shown that intermolecular charge transfer occurs in the ground state of the complex: a charge delocalization of about 10-2 electron from the HAT6 core to TNF is deduced from both Raman and our previous NMR measurements [L. A. Haverkate, M. Zbiri, M. R. Johnson, B. Deme, H. J. M. de Groot, F. Lefeber, A. Kotlewski, S. J. Picken, F. M. Mulder, and G. J. Kearley, J. Phys. Chem. B 116, 13098 (2012)], implying the presence of permanent dipoles at the donor-acceptor interface. A combined analysis of density functional theory calculations, resonant Raman and UV-VIS absorption measurements indicate that fast relaxation occurs in the UV region due to intramolecular vibronic coupling of HAT6 quinoidal modes with lower lying electronic states. Relatively slower relaxation in the visible region the excited CT-band of the complex is also indicated, which likely involves motions of the TNF nitro groups. The fast quinoidal relaxation process in the hot UV band of HAT6 relates to pseudo-Jahn-Teller interactions in a single benzene unit, suggesting that the underlying vibronic coupling mechanism can be generic for polyaromatic hydrocarbons. Both the presence of ground state CT dipoles and relatively slow relaxation processes in the excited CT band can be relevant concerning the design of DLC based organic PV systems. [ABSTRACT FROM AUTHOR]