ANALYTICAL ASPECTS OF PLASMA PENCIL UTILIZATION


Magda DVOŘÁKOVÁ^1, Aleš HRDLIČKA^1,2, Pavel SLAVÍČEK^3, Viktor KANICKÝ^1,2

^

^1 Department of Chemistry, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech
Republic

^2 Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech
Republic

^3 Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, 611 37
Brno, Czech Republic


Plasma pencil is a capacitively coupled rf jet discharge operated in argon, helium or gas mixtures
at the atmospheric pressure. It was originally designed for surface modifications of cultural
heritage objects. It has been also tested in analytical spectrochemistry [1, 2] as an alternative
excitation source. Due to lower excitation temperatures of about 3700-4000 K it exhibits matrix
interferences by easily ionisable elements (EIE) [3] and possible influence of anions from
dissociated salts is investigated. E.g. the influence of EIE on Cu and Zn emission is apparently
driven by excitation energies of Cu and Zn lines and ionization energies of EIE. However, the
depression effect of sulfates on Zn emission is unexpectedly stronger than on Cu emission [4]. To
find out if a plasma pencil can be used as an alternative excitation source drinking water samples
were analyzed. The standard addition method and the calibration method were used for sodium,
magnesium, potassium and calcium cations content determination. ICP-OES was also employed for the
same experiments. Can be said that the results of the two discharges do not differ significantly.


References

[1] L. Novosád, A. Hrdlička, P. Slavíček, V. Otruba, V. Kanický, Plasma pencil as an excitation
source for atomic emission spectrometry, J. Anal. At. Spectrom., 27 (2012), pp. 305-309.

[2] L. Novosád, A. Hrdlička, P. Slavíček, V. Otruba, V. Kanický, Possibilities and analytical
properties of the radiofrequency plasma pencil operating in the continuous and in the pulsed mode,
J. Anal. At. Spectrom., 30 (2015), pp. 459-467.

[3] M. Dvořáková, A. Hrdlička, P. Slavíček, V. Kanický, V. Otruba, Effects of easily ionisable
elements on copper and zinc lines excited in a plasma pencil, J. Anal. At. Spectrom., 31 (2016),
pp. 2031-2036.

[4] M. Dvořáková, A. Hrdlička, P. Slavíček, V. Kanický, Effects of acid, sodium and its salt
counterions on the atomic emission of copper and zinc excited in plasma pencil, J. Anal. At.
Spectrom., 34 (2019), pp. 2451-2458.


Acknowledgements

This work was financially supported by the Ministry of Education, Youth and Sports of the Czech
Republic under the project CEITEC 2020 (LQ1601) under the National Sustainability Programme II, by
the project CZ.1.05/2.1.00/03.0086 funded by the European Regional Development Fund and project
LO1411 (NPU I) funded by Ministry of Education Youth and Sports of the Czech Republic, and by the
project MUNI/A/1375/2018.