The role of oxygen in a large area of RF-powered atmospheric pressure dielectric barrier glow discharge plasma in sterilization

• A nonequilibrium Ar/O2 plasma at atmospheric pressure was generated between two parallel square electrodes by a 13.56-MHz power supplier. Experimental results demonstrate that the Ar/O2 plasma more effectively kills Staphylococcus aureus and Escherichia coli than the Ar plasma. When the O2 flow rate increases from 0 to 100 sccm step by step, the discharge voltage and the radio-frequency (RF) current always show sinusoidal waveforms, and the discharges maintain the α mode as well. In addition, the sterilization efficiency values of the RF-powered atmospheric pressure Ar/O2 plasma depend on the oxygen fraction in Ar gas. It is found that the sterilization efficiency of the Ar/O2 plasma is highest with 0.5 vol.% oxygen in argon gas, corresponding to the maximum production of O(3P) radicals. It is considered that the O(3P) radicals produced by the Ar/O2 plasma play a significant role in atmospheric plasma sterilization.

Ämnesord

NATURVETENSKAP  -- Fysik -- Fusion, plasma och rymdfysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Fusion, Plasma and Space Physics (hsv//eng)

Nyckelord

Oxygen radicals

radio-frequency (RF)-powered atmospheric pressure plasma

sterilization mechanisms

Ar plasmas

Argon gas

Atmospheric plasmas

Dielectric-barrier glow discharges

Discharge voltages

Non equilibrium

Oxygen fractions

Oxygen radical

Power suppliers

Radio frequencies

Rate increase

Sinusoidal waveforms

Staphylococcus aureus

Step-by-step

Argon

Atmospheric pressure

Atmospherics

Bacteria

Escherichia coli

Glow discharges

Oxygen

Sterilization (cleaning)

Plasmas

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)