Reduced pressure argon plasma

Deposition of copper metal Since Cu(II) is the preferred oxidation state of copper, Cu2+ salts are more stable and more available, hence, in a technical application it would be favorable to use them as starting material. We tried to reduce Cu(CF3S03)2 dissolved in [EMIM][TfO], [BMP][TfO] and [BMIM][TfO] with an argon plasma (gas pressure 100 Pa) as well as with a nitrogen plasma (100 Pa), respectively. Additional experiments with Cu(CF3SC>3)2 dissolved in [EMIM][TfO] and Ar/H2 plasmas were carried out, with the distance between the hollow cathode in the gas phase and the surface of the ionic liquid metal salt solution being 3, 45 and 100 mm. Moreover, for the 3 mm distance several experiments with different gas pressures from 50 to 500 Pa were carried out. 

The glow discharge (GD) is a reduced-pressure gas discharge generated between two electrodes in a tube filled with an inert gas such as argon. The sputtered atom cloud in a GD source consists of excited atoms, neutral atoms, and ions. The emission spectrum can be used for emission spectrometry in the technique of GD-OES, but the GD source can also be used for AAS, AFS, and MS. The source can be used with any of the types of spectrometers discussed for plasma emission sequential monochromator, Rowland circle polychromator, echelle spectrometer, or combination sequential-simultaneous designs. The detectors used are the same as described for plasma emission spectrometry PMTs, CCDs, or CIDs. 

The development of many alternative plasma sources has led to a resurgence of analytical atomic emission spectroscopy in recent years. The major plasma emission sources used for gas chromatographic detection have been the microwave-induced helium plasma, under atmospheric or reduced pressure (MIP), and the DC argon plasma (DCP). The inductively coupled argon plasma (ICP) has been used much less for GC than as an HPLC detector [4]. 

An argon or helium plasma is sustained in a microwave cavity which serves to focus or couple power from a microwave source, usually operated at 2.45 GHz, into a discharge cell which is a capillary tube, made of quartz, boron nitride, alumina etc.. Microwave plasmas of different cavity designs may be operated at atmospheric or under reduced pressures [12, 13]. The 50-100 watt power levels for analytical microwave plasmas are much lower than for the DCP or the ICI giving... 

The first GC-microwave-induced plasma emission system was reported in 1965 [23]. During the past two decades GC-plasma emission systems have gained in popularity and have been used for the identification and quantification of mercury, lead, tin, selenium, and arsenic compounds [13]. The most frequently used plasma source is the microwave-induced plasma operated either at reduced pressure or at atmospheric pressure with helium or argon as the plasma gases at powers of 100 to 200 W The Beenakker cylindrical resonance cavity introduced in 1976 [24], and since then modified to achieve better detection limits, is most frequently used in the GC-microwave-induced plasma emission systems that are easily adaptable to capillary GC operation. These microwave-induced plasma detectors respond to non-metals (H, D, B, C, N, O, F, Si, F S, Cl, As, Se, Br, I) and metals, with absolute detection limits in... 

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