Neutral Metal 1,2-Dithiolenes: Preparations, Properties and Possible Applications of Unsymmetrical in Comparison to the Symmetrical

This paper is an overview concerning the preparations and properties as well as possible applications of neutral (one component) metal 1,2-dithiolenes (and selenium analogues). The structural, chemical, electrochemical, optical and electrical behavior of these complexes depend strongly on the nature of ligand and/or the metal. The results of unsymmetrical in comparison to those of symmetrical complexes related to the properties of materials in the solid state are primarily discussed. The optical absorption spectra exhibit strong bands in the near IR spectral region ca. 700 to ca. 1950 nm. X-ray crystal structure solutions show that the complexes usually have square-planar geometry with S–S and/or M–S contacts. Some of them behave as semiconductors or conductors (metals) and are stable in air. The cyclic voltammograms at negative potentials are different from the corresponding potentials of tetrathiafulvalenes (TTFs). As a consequence, the LUMO bands occur at much lower levels than those of TTFs. Consequently, electrical measurements under conditions of field effect transistors exhibit n-type or ambipolar behavior. Illumination of materials with high power lasers exhibits non-linear optical behavior. These properties enable metal 1,2-dithiolene complexes to be classified as promising candidates for optical and electronic applications, (e.g., saturable absorbers, ambipolar inverters)

Laser Scribing of Thin Films Relevant for the Second Generation, Large Scale Monolithic Photovoltaic Solar Cells

Date du colloque : 09/2013International audienc

Fusion of Synchronous Fluorescence Spectra with Application to Argan Oil for Adulteration Analysis

When synchronous fluorescence (SyF) spectroscopy is used for quantitative and qualitative analysis, selection of a useful wavelength interval between the excitation and emission wavelengths (Δλ) is needed. Presented is a fusion approach to combine Δλ intervals thereby negating the selection process. This study uses the fusion of SyF spectra to detect adulteration of argan oil by corn oil and quantitative analysis of the corn oil content. The SyF spectra were acquired by varying the excitation wavelength in the region 300-800 nm using Δλ wavelength intervals from 10 to 100 nm in steps of 10 nm producing 10 sets of SyF spectra. For quantitative analysis, two calibration approaches are evaluated with these 10 SyF spectral datasets. Multivariate calibration by partial least squares (PLS) and a univariate calibration process where the SyF spectra are summed over respective SyF spectral ranges, the area under the curve (AUC) method. For adulteration detection and quantitation of the corn oil, prediction errors decrease with fusion compared to individually using the 10 Δλ interval SyF spectral data sets. For this data set, the AUC method generally provides smaller prediction errors than PLS at individual Δλ intervals as well as with fusion of all 10 Δλ intervals

Low cost and high efficient, second generation thin film solar cells

Date du colloque : 09/2014International audienc

Hexane-1,6-diammonium bis­(pyridine-2-carboxyl­ate)

The title compound, C6H18N2 2+·2C6H4NO2 −, consists of a doubly protonated hexa­methyl­enediammonium dication and two pyridine-2-carboxyl­ate anions. These ions inter­act by means of inter­molecular N—H⋯O and N—H⋯N hydrogen bonds to form a two-dimensional array. The carboxyl­ate groups of the anions appear to be delocalized on the basis of the C—O bond lengths

Measurement of Charge Carrier Mobility in Perovskite Nanowire Films by Photo-Celiv Method

In this paper the holes\u27 mobility for the configuration FTO/TiO 2 /CH 3 NH 3 PbI 3 /Spiro-MeOTAD/Au was measured for the first time by the Photo-CELIV method. The TiO 2 dense film was deposited by reactive sputtering at room temperature on FTO glass substrates. High crystalized perovskite films were deposited from solutions in one step by spin coating. Spiro-MeOTAD molecular glass was used as holes transporting layer. The highest holes\u27 mobility from TiO 2 thin film through the perovskite and Spiro MeOTAD film to the top gold electrode was of order 8.5×10-7 cm 2 /Vs. Measurement of charge carrier mobility in perovskite nanowire films by photo-celiv method