International audienceThe formation of a passivation film (solid electrolyte interphase, SEI) at the surface of the negative electrode of full LiCoO2/graphite lithium-ion cells using LiPF6 (1M) in carbonate solvents as electrolyte was investigated by means of x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The analyses were carried out at different potentials of the first and the fifth cycles, showing the potentialdependent character of the surface-film species formation. These species were mainly identified as Li2CO3 up to 3.8 V and LiF up to 4.2 V. This study shows the formation of the SEI during charging and its partial dissolution during discharge. Copyright © 2005 John Wiley & Sons, Ltd

X-ray photoelectron valence spectra of lithium salts LiBF4, LiPF6, LiTFSI, and LiBETI have been recorded and analyzed by means of density functional theory (DFT) calculations, with good agreement between experimental and calculated spectra. The results of this study are used to characterize electrode/electrolyte interfaces of graphite negative electrodes in Li-ion batteries using organic carbonate electrolytes containing LiTFSI or LiBETI salts. By a combined X-ray photoelectron spectroscopy (XPS) core peaks/valence analysis, we identify the main constituents of the interface. Differences in the surface layers' composition can be evidenced, depending on whether LiTFSI or LiBETI is used as the lithium salt.

and cycling ability high. Most of the studies in the field were performed on electrical double layer capacitors or on EC based on pseudocapacitive transition metal oxides (MnO 2 , RuO 2 , FeWO 4 ). Pseudocapacitance is used to explain the charge storage mechanism in a capacitive electrode where the storage process arises from fast redox reactions with no phase transformation of the electrode material. Pseudocapacitance is Faradaic in origin, involving the passage of charge across the double layer, as in battery charging or discharging, but capacitance arises on account of the special relation that can originate for thermodynamic reasons between the extent of charge acceptance (ΔQ) and the change of potential (ΔV), so that a derivative d(ΔQ)/d(ΔV), which is equivalent to a capacitance, can be formulated and experimentally measured by dc, ac, or transient techniques. While this process is basically different from ion accumulation in porous carbon electrodes, the signature of the pseudocapacitive material is characterized by triangular shape constant current charge/discharge plots and quasirectangular shape cyclic voltammograms. Only a few number of papers focused on nitride-based supercapacitors although, Conway [2] et al. demonstrated in 1988 the potential use of molybdenum nitride pseudocapacitive material acting as an efficient electrode for electrochemical capacitors.Micro-supercapacitors (MSC) are considered as promising miniaturized electrochemical energy storage devices for Internet of Things applications. Unfortunately, the technological readiness level of these devices is still at the lab scale with the development of individual prototypes due to the difficulty to produce high performance porous electrode material with microelectronic equipment available in pilot production lines. Here, the collective fabrication of on chip MSC based on sputtered porous vanadium nitride (VN) bifunctional material is reported. For the first time in the field of MSC, the porosity of the sputtered VN thin films is fine-tuned at the nanoscale level in order to produce high capacitance and high conductive electrodes. Interdigitated MSC based on optimized VN thin films are fabricated on silicon wafers using microelectronic facilities. 2 μWh cm −2 /10 mWh cm −3 energy densities are reached while keeping a high power density (10 mW cm −2 />50 W cm −3 ) owing to high electrical conductivity of VN layers. Sputtered vanadium nitride thin films are demonstrated to be suitable pseudocapacitive electrodes and highly conductive current collectors for MSC applications. These findings represent a major advance in order to go toward the large-scale deployment of such miniaturized power sources. Micro-SupercapacitorsThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.

The first photoswitchable bimetallic gold catalysts based on an azobenzene backbone have been synthesized and their catalytic properties have been investigated.

A simple synthetic method allows the one-pot assembly of C3 -symmetric, 44-core-valence-electron, triangular Pd or Pt clusters and their heterobimetallic mixed Pd/Pt analogues. These mixed metal complexes are the first examples of stable triangular all-metal heteroaromatics. In contrast to traditional heteroaromatic molecules formed combining main-group elements, they actually retain structural and electronic features of their homonuclear analogues.

With the aim of discovering new cytotoxic prenylated stilbenes of the schweinfurthin series, Macaranga tanarius was selected for detailed phytochemical investigation among 21 Macaranga species examined by using a molecular networking approach. From an ethanol extract of the fruits, seven new prenylated stilbenes, schweinfurthins K-Q (7-13), were isolated, along with vedelianin (1), schwenfurthins E-G (2-4), mappain (5), and methyl-mappain (6). The structures of the new compounds were established by spectroscopic data analysis. The relative configurations of compounds 8, 12, and 13 were determined based on ROESY NMR spectroscopic analysis. The cytotoxic activities of compounds 1-13 were evaluated against the human glioblastoma (U87) and lung (A549) cancer cell lines.

OATAO is an open access repository that collects the work of some Toulouse researchers and makes it freely available over the web where possible.

Replacing aromatic donor ligands with cationic Pd3 + complexes.