Research On The Qualitative Detection Of CO₂?SO₂?NO₂ By Micro-ICP Excitation Source

A new type of low-pressure discharge micro-ICP excitation source based on PCB technology was developed by our research group in previous research.The micro-ICP excitation source combined with Aventis micro fiber spectrometer explored its excitation ability and excitable sample.Prophase work successfully inspired methane,acetylene,ammonia,nitrogen and other samples.The aim of present study is to explore the ability of the micro-excitation source to detect more new gas samples.The main work of this paper is as follows:The micro-ICP excitation source prototype was used to investigate the excitation performance of CO₂,SO₂ and NO₂ gas samples for the first time.These three kinds of gas were successfully excited into plasma in experiments,when the argon is used as the carrier gas,and the spectrum was obtained by micro fiber spectrometer.The spectrum were identified a total of 20 lines including C+ 398.30 nm,O+ 379.45 nm and CO 394.6nm,a total of 9 lines including S 675.72 nm,O 794.75 nm,and a total of 22 lines including N+ 545.21 nm,O+ 432.86 nm and NO₂+ nm by Sepcline data base.Experiments showed that the new micro ICP excitation source has the ability to stimulate CO₂,SO₂ and NO₂ and can be used for the qualitative analysis of these three gases.The three samples used in the experiment are gas;CO₂ and SO₂ were self-made,and NO₂ was produced by professional manufacturers.CO₂ gas samples were produced by the reaction of limestone and dilute hydrochloric acid;SO₂ gas was produced by the reaction of concentrated sulfuric acid and sodium sulfite.The optimum working parameters of the excitation source microcircuit module were studied by using CO₂ gas as the excitation sample.The microcircuit module of 12 kinds of planar spiral coils were combined with three kinds of turns,two kinds of space between turns and two kinds of outer diameter.Experiments showed that the microcircuit component which has three-turn and 10 mm outer diameter have the best stimulate results.The paper discussed that RF power and air pressure has effects on the spectral intensity and electron temperature between by CO₂ gas sample.Experiments showed that the RF power in the range of 5 W 25 W can be excited into plasma.The pressure in the range of 50 Pa 130 Pa has a better excitation effect.At the same time,the plasma's electron temperature were estimated by Double Line of Spectroscopy.The electron temperature is between 1800 K and 3000 K according to the experimental results.