A novel solution cathode glow discharge geometry for improved coupling to optical emission spectrometry

Abstract

The Solution-Cathode Glow-Discharge (SCGD) is an atmospheric pressure glow discharge used for atomic emission spectrometry that is typically sustained between a metallic pin-anode and a liquid cathode, wherein sample solutions...

Trace element analysis in lithium matrices using micro-discharge optical emission spectroscopy

“…In classical ICP-OES, depending on emission line and matrix, linearity ranges of up to 6 orders of magnitude can be achieved 60 and with SCGD 3–5 orders of magnitude. 58 The typical linearity range of micro-discharge OES is illustrated in Fig. 3, using a lithium calibration from 0 to 10 mg L −1 as an example.…”

“…The typical average power consumption is about 200 W (including PC for control and data analysis), which is much less than that required for classical ICP-OES (typically 1–2 kW) 12 and in the range of that required by other micro-plasma techniques. 58 A disadvantage, however, is the relatively high consumption of deionised water needed to dilute the originally concentrated solutions in the linear range. This can currently be as high as 25 Litres on one typical measurement day.…”

“…As a result, molecules are dissociated into atoms and the atoms are subsequently excited in the small volume around the cathode. The emitted light is then transferred to a spectrometer via an optical fibre cable whereby, similar to SCGD, 58 predominantly spectra with neutral atomic lines are obtained. During a single analytical measurement, typically 1000–3000 of approx.…”

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…Sample solutions are introduced to the GD as a flowing stream from a cylindrical capillary. Hazel et al 50 described a system which sustained the SC-GD plasma in a horizontal arrangement between a flat anode and a liquid cathode constructed from a thin, rectangular capillary from where the liquid emerged. This arrangement created a sheet-like plasma where the negative glow of the SC-GD approximated the shape of the entrance slit of the spectrometer, improving the efficiency of optical sampling.…”