“…The gas sources, such as O 2 [5,7,23], air [6,15], N 2 [26], O 3 [2,[9][10][11][12], O 2 /N 2 mixture [27,28] and argon [7,24,28], present in aqueous pulsed discharge plasma process highly affected the formation of the active species and the removal of the organic pollutants, so O 2 , N 2 , and air (atmosphere) in our work were selected as the gas sources to be investigated. The initial experimental conditions were similar to those above optimum experimental conditions, except for gas source.…”