At ASDEX upgrade (AUG) a new framework for the evaluation of impurity densities based on measurements from charge exchange recombination spectroscopy (CXRS) diagnostics has been developed. The charge exchange impurity concentration analysis code, or CHICA, can perform these calculations for all of the beam-based CXRS diagnostics at AUG and is equipped with the atomic data for all of the regularly measured charge exchange spectral lines (He, Li, B, C, N, O, and Ne). CHICA includes four different methods for the evaluation of the neutral density populations, which feature different implementations and contain varying levels of sophistication. These methods have been thoroughly benchmarked against one another, enabling the important processes for the evaluation of neutral densities to be identified as well as the neutral populations that are most critical to the accurate interpretation of the measured CXRS intensities. For the AUG neutral beams, charge exchange with the ground state of the first energy component is typically the dominant contribution to the measured CXRS intensities, but emission from reactions with the n=2 beam halo population can contribute up to 35% to the total signal and must be included in the analysis. Neglect of this population leads to incorrect magnitudes and incorrect profile shapes of the calculated impurity density profiles. The edge lines of sight (LOS) of the core CXRS diagnostics at AUG intersect the edge pedestal inside of the neutral beam volume. Therefore, the impurity density is not constant along the LOS, complicating the interpretation of the measured intensities. Within CHICA a forward model for the edge impurity densities has been implemented, enabling the reconstruction of accurate edge profiles.

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CuInS 2 has become a popular and promising candidate as an absorber material in photovoltaic devices and photo-electrochemical cells. Here we report the successful L-cysteine-assisted growth of homogeneous, nanostructured CuInS 2 thin films deposited on fluorine-doped tin oxide coated glass. In contrast to existing synthesis routes using thioacetamide as a sulfur source, our method offers the advantage of being environmentally friendly and non-toxic. We found that L-cysteine is able to reduce the Cu 2+ ions of the precursor CuSO 4 to Cu + in aqueous solution, thus enabling the formation of CuInS 2 thin films. By varying the concentration of the reaction solution during the solvothermal synthesis route, we obtained CuInS 2 films with different thicknesses and compositions, investigated with the help of energy dispersive X-ray spectroscopy with scanning and transmission electron microscopy. X-ray and electron diffraction experiments of the films prove the synthesis of a pure CuInS 2 phase with the chalcopyrite structure except for the highest L-cysteine concentration where additional In 2 S 3 forms. UV-Vis absorption spectroscopy reveals absorption over the whole visible spectrum. The calculated band gap using the UV-Vis data ranges between 1.4 and 1.5 eV, and can be adjusted by changing crystal size and chemical composition. This offers a promising route towards tuning the optical and transport properties. First dye degradation experiments show promising activity under solar illumination.

Abstract:Three new derivatives of methoxyphenyl-substituted bis(picolyl)phosphines 3-5, the CH 2 TMS substituted bis(picolyl)phosphine (6) and related phosphine oxides 2b-5b have been synthesized. Syntheses were accomplished by reacting the corresponding dichlorophosphines with picolylTMS (7). An improved synthesis of most of the starting materials is also presented and enables increased ligand yields in all cases. The new bis(picolyl)phosphines and phosphine oxides are extensively

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We present a facile two-step synthesis of vanadium (III) oxide/ carbon core/shell hybrid material for application as lithium-ion battery electrode. The first step is a thermal treatment of a mixture of vanadium carbide (VC) and NiCl 2 · 6H 2 O at 700 8C in an inert gas atmosphere. Elemental nickel obtained from decomposing NiCl 2 · 6H 2 O served as a catalyst to trigger the local formation of graphitic carbon. In a second step, residual nickel was removed by washing the material in aqueous HCl. By replacing NiCl 2 · 6H 2 O with anhydrous NiCl 2 , we obtained a hybrid material of vanadium carbide-derived carbon and a vanadium carbide core. Material characterization revealed a needle-like morphology of the rhombohedral V 2 O 3 along with two carbon species with a different degree of graphitic ordering. We varied the NiCl 2 · 6H 2 O-to-VC ratio, and the optimized material yielded a capacity of 110 mAh · g À1 at 2.5 A · g À1 which increased to 225 mAh · g À1 at 0.1 A · g À1 after 500 cycles in the potential range of 0.01-3.00 V vs. Li/Li + . This enhanced performance is in stark contrast to the loss of lithium uptake capacity when using commercially available V 2 O 3 mixed with carbon black, where 93 % of the initial capacity was lost after 50 cycles.

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