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Sulfide‐based solid electrolytes (SEs) are amongst the most promising solid electrolytes for the development of solid‐state batteries (SSBs) due to their high ionic conductivity and processing advantage over oxide‐based SEs. However, one of the main drawbacks of sulfide SEs is their rapid degradation in presence of humidity. In this study, we investigated the effect of exposing three different sulfide SEs (Li7P3S11, the argyrodite Li6PS5Cl and the chloride‐doped argyrodite Li6‐xPS5‐xCl1+x) to the atmosphere of a dry room at a dew point (DP)=−40 °C. For the first time to the best of our knowledge, enhanced infra‐red (IR) laser technology was employed to follow and quantify online and in‐situ H2S evolution by the SEs in a dry room environment over 16 h. It was found that argyrodite compounds evolved approximately 8 times less H2S compared to Li7P3S11 over 16 h of exposure with peak concentrations between 5 and 16 ppm vol. The exposed materials were studied using X‐ray diffraction, Raman spectroscopy, electrochemical impedance spectroscopy, X‐ray photoelectron spectrometry (XPS) and galvanostatic cycling. XPS results revealed a formation of Li2CO3 on the surface of argyrodite SEs, which served as a robust passivation layer limiting considerably reactions with the dry room atmosphere. [ABSTRACT FROM AUTHOR]

This work describes the synthesis and characterization of two new bis-terdentate Ru(ii) complexes. Compound 1is a homoleptic complex containing two CNC N-heterocyclic carbene (NHC) based ligands, whereas compound 2bears one CNC ligand and an ancillary terpyridine ligand. The redox and photophysical properties of both compounds have been investigated and their X-ray crystal structures determined. Complex 1displays a close-to-perfect octahedral coordination geometry and is not luminescent at room temperature while complex 2features room temperature and 77 K luminescence despite its partially distorted geometry. The presence of the NHC moieties brings a significant amount of electronic density to the metal centre therefore lowering its oxidation potential with respect to that of analogous polypyridyl complexes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Modeling TD-DFT reproduction of X-ray strusctures and absorption spectra. [•] Formulating computationally cheap supporting design of photochemical molecular devices. [•] PDOS prediction of luminescence and non-luminescence in complexes. [Copyright &y& Elsevier]

A new method based on the electrochemical oxidation of thiols was used to easily generate multilayer assemblies of coordination complexes on a gold surface. For this purpose, two complexes bearing two anchoring groups for surface attachment have been prepared: [Ru(tpySH)(2)](2+) (1) and [Fe(tpySH)(2)](2+) (2) (tpySH = 4'-(2-(p-phenoxy)ethanethiol)-2,2':6',2″-terpyridine). Cyclic voltammetry of 1 in CH(3)CN exhibits two successive oxidation processes. The first is irreversible and attributed to the oxidation of the thiol substituents, whereas the second is reversible and corresponds to the 1 e(-) metal-centered oxidation. In the case of 2 both processes are superimposed. Monolayers of 1 or 2 have been formed on gold electrodes by spontaneous adsorption from micromolar solutions of the complexes in CH(3)CN. SAMs (self-assembled monolayers) exhibit redox behavior similar to the complexes in solution. The high surface coverage value obtained (Γ = 6 × 10(-10) and 4 × 10(-10) mol cm(-2) for 1 and 2, respectively) is consistent with a vertical orientation for the complexes; thus, one thiol is bound to the gold electrode, with the second unreacted thiol moiety exposed to the outer surface. Successive cyclic voltammetry induced a layer-by-layer nanostructural growth at the surface of the SAMs, and this is presumably due to the electrochemical formation of disulfide bonds, where the thiol moieties play a double role of both an anchoring group and an electroactive coupling agent. The conditions of the deposition are studied in detail. Modified electrodes containing both 1 and 2 alternatively can be easily prepared following this new approach. The film proved to be stable, displaying a similar current/voltage response for more than 10 repeating cycles in oxidation up to 0.97 V vs Ag/AgNO(3) (10(-2) M).