7th Asia-Pacific Conference on Plasma Physics, 12-17 Nov, 2023 at Port Messe Nagoya

Atmospheric pressure discharge plasma - atomic emission spectroscopy used forelemental analysis
1

Hao Yuan1, De-zheng Yang1, Jie Zhang1
Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Dalian Universityof Technology), Ministry of Education, Dalian 116024, Chinae-mail: yuanhao@dlut.edu.cn

Elemental analysis is a technique used to determine theelements and their content of sample, which is widely
applied in deep space exploration, geological exploration,
environmental monitoring.[1] The most common methodof elemental analysis is ICP-AES/MS, which has a good
detection stability and sensitivity. However, ICP-AES/MS
is only suitable for operating in laboratory, and cannot be
used for in-situ elemental analysis, because it cost muchinert gas, can only detect liquid sample, and have the highenergy consumption. Recently, LIBS was introduced intoelemental analysis, which can detect solid sample, anddon’t need special gas.
The basic principle of ICP-AES/MS and LIBS for
elemental analysis is atomizing the tested element in thesample by the high temperature and particle bombardmentof plasma, and the generated atoms are excited or ionized,
and the excited atoms or ions are detected by the emission
spectrometer or mass spectrometer.[2] Based on thisprocess, atmospheric pressure discharge plasma can also
be applied for elemental analysis in theory. It presents agreat potential in portable use, rapid detecting and in-situ
analysis, depending on its advantages of simple operation,
low cost of equipment, and miniaturization of devices.[3]However, similar with ICP-AES, atmospheric pressure
discharge plasma was mainly used for detecting liquidsample. It is because that metallic elements usually exist
in liquid in the form of ions. However, solid samples havea more stable structure and lower chemical activity, andmetallic elements exist in the form of crystals, so it is moredifficult to be atomized, requiring plasma with higher gas
temperature, more energy injection and more abundantactive particles.
In our studies, the metallic elements both in liquid andsolid were detected by pulsed electrolyte cathodedischarge, atomization discharge and needle-needle bareelectrode arc discharge. The detecting limits of Cd, Cu, Feand Pb were measured, in the level of 0.01 μg/mL in liquidsample, and in the level of 0.01 μg/g in solid sample.
Importantly, temporal resolved spectra were employed tofilter spectral interference, which are mainly sourced by
the spectral bands of OH (A2Σ–X2Π) and N2 (C3Πu–B3Πg).
As a result, the detection sensitivity of elemental analysis
was improved significantly.
This work is supported by the National Natural Science
Foundations of China (Grant No. 52077026), and theChina Postdoctoral Science Foundation (Grant No.
2022M710590).

References[1] J.R. Bacon, et al, J. Anal. At. Spectrom. 38, 10 (2023).
[2] S. Mushtaq, et al, J. Anal. At. Spectrom. 37, 985(2022).
[3] P. Pohl, et al, TrAC Trend Anal. Chem. 88, 119 (2017).

Figure 1. The schematic diagram of pulsed electrolyte cathode discharge – atomic emission spectroscopy used forelemental analysis.