Excitation Wavelength and Temperature at Irradiation of Metal by Atmospheric-Pressure Nonequilibrium Argon Plasma

Abstract

We studied excitation wavelength and temperature during irradiation of atmospheric-pressure nonequilibrium argon plasma to pure metal plate. We observed excitation emission of light activated by argon plasma in the same wavelength region, both with and without metal plate. The wavelength region activated by atmospheric-pressure nonequilibrium argon plasma was limited. In the presence of the ion corresponding to wavelength region activated by argon plasma, corresponding ions were activated. Both oxygen ions and metal ions are generated by plasma irradiation, but during each observed wavelength, the wavelength of metal ion activated by argon plasma was dominant, because excitation energy of oxygen ion is greater than that of each metal ion. Heat propagation from argon plasma to metal plate occurs by plasma irradiation. Consequently, heat propagation from argon plasma to copper plate is greater in comparison to cases with other metal plates. This is due to the high thermal conductivity of copper. In the case of atmospheric-pressure nonequilibrium plasma, plasma is affected by interaction with an object, because plasma energy is smaller, and temperature of nonequilibrium plasma changes via with thermal conductivity of the object.

Experimental investigation of a ns-pulsed argon plasma jet for the fast desorption of weakly volatile organic compounds deposited on glass substrates at variable electric potential

“…Besides, we also reported that the absolute density of Ar(1s5) metastables depends on the permittivity of the substrate when maintained at a floating potential, increasing with the permittivity of the plate [4]. Regarding the works published by other groups, the interaction of a kHz sinusoidal Ar APPJ with different metal plates (at floating potential) resulted in a noticeable increase of the intensities of the emission spectra of the APPJ [26]. On top of that, it was found that an rf-driven Ar APPJ does not penetrate into a thin capillary tube (inner diameter=250 μm) when the tube is maintained at a floating potential; but the placement of a grounded metallic ring downstream of the capillary orifice allows for the jet to penetrate inside the tube [24].…”

“…For Ar APPJs, numerous works can be found referring mostly to the surface modification of polymeric materials [19][20][21][22]. Contrary to He jets, fewer studies focusing on the dynamics of Ar APPJs impinging on substrates have been published so far [2,4,13,[23][24][25][26][27]. Among them, the improvement of the stability of a ns-pulsed APPJ when impinging on a floating-potential glass plate was reported lately by our group [2,27].…”