Regular Article

The formation mechanism of aqueous hydrogen peroxide in a plasma-liquid system with liquid as the anode^★

¹ Institute of Electromagnetics and Acoustics, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, Xiamen 361005, P.R. China
² State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400044, P.R. China
³ Key Laboratory of Special Function Materials & Structure Design of the Ministry of Education, and School of Physical Science & Technology, Lanzhou University, Lanzhou 730000, P.R. China
⁴ Department of Electrical and Computer Engineering, Duke University, Durham, NC 27708, USA
⁵ School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD 4000, Australia
⁶ CSIRO-QUT Joint Sustainable Processes and Devices Laboratory, P.O. Box 218, Lindfield, NSW 2070, Australia

^a e-mail: chenqiang@xmu.edu.cn

Received: 29 July 2019
Received in final form: 29 December 2019
Published online: 23 April 2020

Abstract

We investigate the formation of aqueous hydrogen peroxide (H₂O_2aq) in a DC discharge plasma-liquid system with liquid as the anode. The theoretical analysis and experimental results show that the H₂O_2aq formation process is mostly controlled by the aqueous electron-induced reactions in the liquid zone directly affected by the plasma. It is shown that the low H₂O_2aq yield in this system is caused by quenching the dissolved OH radicals through aqueous electrons and alkalization in the plasma-directly-affected liquid zone.