Application of prominent spectral lines in the 125–180 nm range for inductively coupled plasma optical emission spectrometry

Abstract

A new axially viewed ICP optical emission spectrometer featuring an argon-filled optic and CCD detectors was evaluated for the application of prominent spectral lines in the 125–180 nm range. This wavelength range was investigated for several analytical applications of inductively coupled plasma optical emission spectrometry (ICP–OES). There are different advantages for the application of spectral lines below 180 nm. A number of elements, such as Al, Br, Cl, Ga, Ge, I, In, N, P, Pb, Pt, S and Te, were found to have the most intense spectral lines in the wavelength range from 125–180 nm. Compared with lines above 180 nm higher signal-to-background ratios were found. Low limits of detection using pneumatic nebulization of aqueous solutions for sample introduction were calculated for Al II 167.080 nm (0.04 µg L^–1), Br I 154.065 nm (9 µg L^–1), Cl I 134.724 nm (19 µg L^–1), Ga II 141.444 nm (0.8 µg L^–1), Ge II 164.919 nm (1.3 µg L^–1), I I 142.549 nm (13 µg L^–1), In II 158.583 nm (0.2 µg L^–1), P I 177.500 nm (0.9 µg L^–1), Pb II 168.215 nm (1.5 µg L^–1), Pt II 177.709 nm (2.6 µg L^–1), S I 180.731 nm (1.9 µg L^–1) and Te I 170.00 nm (4.6 µg L^–1). Numerous application examples for the use of those lines and other important spectral lines below 180 nm are given. Because of fewer emission lines from transition elements, such as Fe, Co, Cr, lines below 180 nm often offer freedom from spectral interferences. Additional lines of lower intensity for the determination of higher elemental concentrations are also available in the vacuum ultraviolet spectral range. This is specially useful when the concentrations are not in the linear range of calibration curves obtained with commonly used lines.