Chip-based ingroove microplasma with orthogonal signal collection: new approach for carbon-containing species detection through open air reaction for performance enhancement

Abstract

A novel microplasma generator based on ceramic chips has been developed and coupled with optical emission spectrometry through orthogonal detection. Stable microplasma was generated between two electrodes in the ingroove discharge chamber and the optical fiber was set in perpendicular to the gas outlet to collect emitted light. The emission signal of CN is surprisingly enhanced by reacting carbon-containing species with back-diffusion nitrogen from open air, and the enhanced CN signal is successfully applied to sensitively detect organic compounds for the first time. This article focuses to study the structural characteristic and the signal enhancement mechanism through back-diffusion reaction. Several organic compounds were detected directly with the limits of detection down to ppb level. Besides, the advantages of low energy consumption and the chip-based discharge chamber show great potential to be applied in portable devices. This development may lead to a new way for the sensitive detection of organic compounds.

Triboelectric microplasma powered by mechanical stimuli

“…Though the absolute intensity of UV is very low, when the fiber is put very close to the end of the capillary, the relative intensity in UV region is high enough to be detected even in the daylight. Benefiting from the good signal-to-noise ratio (SNR), this type of corona discharge would be a promising UV (or other wavelength) light source for the applications of species detection 48 , elemental analysis 49 , micro total analysis system (μ-TAS) 49 and gas chromatography 50 in the future. The intensity of emission spectra changes with the plasma status, as well as the voltage and the current, as shown in Fig.…”

Nitrogen Microplasma Generated in Chip-Based Ingroove Glow Discharge Device for Detection of Organic Fragments by Optical Emission Spectrometry

“…Compared with the common microplasma jet, the ingroove discharge chamber can improve the microplasma stability through reducing the flow rate of carrier gas, maintaining the microplasma within the two electrodes, and preventing the microplasma from directly contacting the discharge chamber. 35 In addition, the ingroove discharge chamber can improve the detection sensitivity through reducing the size of the gas outlet to prolong the residence time of samples in the microplasma. The discharge chamber also served as the gas buffer chamber to reduce gas fluctuation.…”

“…Therefore, the excitation power of nitrogen microplasma is weaker than that of argon. The C, CH, and C 2 are unstable and easily turned into CN in a nitrogen atmosphere; 35 hence, only an emission line of CN was obtained from the acetone spectrum in nitrogen microplasma. Similar phenomena were also found in the spectra of other organic compounds.…”

“…The microplasma device was designed on the basis of the device reported in our previous works. 35 In brief, the microplasma, including a gas inlet, two electrodes, and an enclosed discharge chamber, was made on a small ceramic baseboard chip (20 mm × 10 mm × 1 mm). A quartz tube was used as the gas inlet.…”

A compact AC-glow discharge-optical emission spectrometer for real-time detection of N2 and Ar in O2 with sub-ppm-level sensitivity

“…There have been some important achievements in gas analysis by optical emission spectroscopy of plasma recently. [7][8][9][10][11][12] Due to pioneering works, real-time, ppb-level detection of multiple gases in the air is close. Among them, we have promoted the sensitive detection of N 2 and Ar in O 2 to sub-ppm level in realtime by employing a highly efficient signal collection optical system and the micro-glow discharge driven by high DC voltage.…”