Improvement of analytical sensitivity by Ar-N2 inductively coupled plasma in axially viewing optical emission spectrometry.
The analytical sensitivities of elements were improved by Ar-N(2) inductively coupled plasma (Ar-N(2) ICP) in axially viewing optical emission spectrometry (OES). A commercially available ICP-OES instrument was used, and only N(2) gas was added at flow rates of up to 1.0 L min(-1) into Ar plasma gas. A stable Ar-N(2) ICP was obtained, and the net signal intensities of elements were enhanced by factors of up to 25 compared to those observed for Ar ICP-OES. The detection limits evaluated were also improved by factors from 5 to 10, especially for elements with relatively higher ionization energies. Moreover, the analytical sensitivities for these elements observed in axially viewing Ar-N(2) ICP-OES were superior to those in radially viewing Ar-N(2) ICP-OES reported previously. The Ar-N(2) ICP is expected to be a useful alternative source for excitation and ionization in axially viewing ICP-OES.
Ohata
Masaki
M
National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8563, Japan. m-oohata@aist.go.jp
Takaku
Yuichi
Y
Inagaki
Kazumi
K
Hioki
Akiharu
A
Chiba
Koichi
K