Characterization of PZT driven plasma discharge operating in atmospheric pressure air.

In this work, a PZT-driven atmospheric pressure plasma discharge is characterized. Experiments are conducted for two electrode configurations: powered PZT–grounded copper and powered PZT–grounded PZT. The piezo material is composed of lead zirconate, lead titanate, and barium titanates. The experiments are conducted from an interelectrode separation distance of ~ 50 um operating in atmospheric pressure air. For both configurations, VI curves are obtained using rms voltage and current data by varying the input voltage from 50 VPP to 150 VPP. The temporal voltage and current waveforms show the current to lead by ~ 10 degrees for the PZT-CU and by ~ 40 degrees for the PZT-PZT configuration. This suggests that the PZT-PZT configuration is more capacitive in nature. The PZT-PZT experiments are conducted to identify the response of the piezo material in the presence of the plasma charge. For this purpose, the voltage and current in the primary and secondary sections of the grounded piezo were measured. In the PZT-PZT configuration, multiple filaments appear, unlike the PZT-CU. Additionally, the grounded PZT has a varying voltage dictated by the plasma charges striking the electrode. Optical emission spectroscopy was conducted to determine the plasma temperature. High-speed imaging of the discharge dynamics reveals distinct plasma surface interaction on the piezo electrode.