Excitation Temperature Measurement in Liquid Electrode Plasma

Abstract

Liquid electrode plasma atomic emission spectrometry (LEP-AES) is a novel elemental analysis method where a sample solution is placed in a small cuvette that has a narrow microchannel at the center. High voltage is applied to the solution from both ends of the cuvette channel, and then microplasma is generated in the channel. The microplasma is employed in atomic emission spectrometry as a plasma source. Excitation temperature was deduced using a Boltzmann plot. The temperature was determined to be 6200 K with a plastic chip at an applied voltage of 800 V. To investigate effects of the experimental conditions on excitation temperature, applied voltage, type of acid, and the shape of the cross section of a microchannel at the center of the cuvette were varied. The excitation temperature was not influenced by applied voltage or type of acid, but was affected by the shape of the cross section of the microchannel.