Effective Electro-Activation Process of Hydrogen Peroxide/Peroxydisulfate Induced by Atomic Hydrogen for Rapid Oxidation of Norfloxacin over the Carbon-Based Pd Nanocatalyst

Abstract

Peroxydisulfate (PDS) can be activated by electrochemistry, for which using atom H* as an activator is feasibly favorable in theoretical and experimental applications. Studies have shown that atomic H* can cleave the peroxide bond as a single-electron reducing agent in Na2S2O8 to generate SO4•−, thus achieving the degradation of pollutants. Herein, Pd nanoparticles synthesized by in an in situ solution were dispersed in carbon black and then loaded on carbon felt, called Pd/C@CF, as the cathode for peroxydisulfate activation. This showed an ideal degradation effect on a small electrode (10 mm × 10 mm). Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) tests were taken to verify the significant increase in the yield of the reduction of Na2S2O8 by H*. The degradation experiments and free-radical scavenging experiment confirmed that the atomic H* was the dominant component triggering the activation of PDS to generate SO4•−. A Pd/C@CF composite electrodes have low pH dependence, high stability and recyclability, etc., which has many potential practical applications in wastewater treatment. In addition, H* can also reduce H2O2 to •OH by breaking the peroxide bond, so the removal of pollutants by the same amount of H2O2 and Na2S2O8 under the same conditions is compared, and their application prospects are analyzed and compared.