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Non-thermal plasmas under atmospheric pressure are of great interest in material surface processing because of their convenience, effectiveness and low cost. In this paper, the treatment of a glass surface for improving hydrophobicity using a non-thermal plasma generated by a dielectric barrier corona discharge (DBCD) with a needle array-to-plane electrode arrangement in atmospheric air is conducted, and the surface properties of the glass before and after the DBCD treatment are studied using contact angle measurement, surface resistance measurement and the wet flashover voltage test. The effects of the plasma dose (the product of average discharge power and treatment time) of DBCD on the surface modification are studied, and the mechanism of interaction between the plasma and glass surface is discussed. It is found that a layer of hydrophobic coating is formed on the glass surface through DBCD treatment, and the improvement of hydrophobicity depends on the plasma dose of the DBCD. It seems that there is an optimum plasma dose for the surface treatment. The test results of thermal ageing and chemical ageing show that the hydrophobic layer has quite stable characteristics.

The characteristics of homogeneous discharge are studied and compared with those of dielectric barrier discharge (DBD) by measuring their electrical discharge parameters and observing their light-emission phenomena. Several factors, including the voltage amplitude, gap distance, electrode configuration and barrier thickness, are experimentally studied to see their effects on the transition of the homogeneous discharge from the stable mode to the unstable mode. The results show that the homogeneous discharge exists only under certain conditions. The important role of the mesh for obtaining the homogeneous discharge is identified through experiments. It is found that the voltage range for maintaining a stable discharge is wider when the barrier thickness is smaller, the gap distance is shorter and the mesh number is greater. It is thought that the corona discharge produced by the wire mesh together with the property of the PET barrier can cause accumulation of charges on the barrier surface, which may provide initial electrons leading to the burst of the homogeneous discharge in the whole air gap when a certain threshold value of the electric field (breakdown value) is exceeded. In view of this assumption, the experimental results for the effects of these factors on the stability of the homogeneous discharge can be qualitatively interpreted.

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