Direct synthesis of hydrogen peroxide from plasma-water interactions

Hydrogen peroxide (H₂O₂) is usually considered to be an important reagent in green chemistry since water is the only by-product in H₂O₂ involved oxidation reactions. Early studies show that direct synthesis of H₂O₂ by plasma-water interactions is possible, while the factors affecting the H₂O₂ production in this method remain unclear. Herein, we present a study on the H₂O₂ synthesis by atmospheric pressure plasma-water interactions. The results indicate that the most important factors for the H₂O₂ production are the processes taking place at the plasma-water interface, including sputtering, electric field induced hydrated ion emission, and evaporation. The H₂O₂ production rate reaches ~1200 μmol/h when the liquid cathode is purified water or an aqueous solution of NaCl with an initial conductivity of 10500 μS cm^-1.