PH-Independent Production of Hydroxyl Radical from Atomic H*-Mediated Electrocatalytic H2O2Reduction: A Green Fenton Process without Byproducts

Huabin Zeng, Gong Zhang, Qinghua Ji, Huijuan Liu, Xin Hua, Hailun Xia, Mika Sillanpää, Jiuhui Qu

Research output: Contribution to journalArticlepeer-review

122 Citations (Scopus)

Abstract

Hydroxyl radical (•OH) can hydroxylate or dehydrogenate organics without forming extra products and is thereby expediently applied in extensive domains. Although it can be efficiently produced through single-electron transfer from transition-metal-containing activators to hydrogen peroxide (H2O2), narrow applicable pH range, strict activator/H2O2 ratio requirement, and byproducts that are formed in the mixture with the background matrix necessitate the need for additional energy-intensive up/downstream treatments. Here, we show a green Fenton process in an electrochemical cell, where the electro-generated atomic H∗ on a Pd/graphite cathode enables the efficient conversion of H2O2 into •OH and subsequent degradation of organic pollutants (80% efficiency). Operando liquid time-of-fight secondary ion mass spectrometry verified that H2O2 activation takes place through a transition state of the Pd-H*-H2O2 adduct with a low reaction energy barrier of 0.92 eV, whereby the lone electron in atomic H∗ can readily cleave the peroxide bridge, with •OH and H2O as products (ΔGr = -1.344 eV). Using H+ or H2O as the resource, we demonstrate that the well-directed output of H∗ determines the pH-independent production of •OH for stable conversion of organic contaminants in wider pH ranges (3-12). The research pioneers a novel path for eliminating the restrictions that are historically challenging in the traditional Fenton process.

Original languageEnglish
Pages (from-to)14725-14731
Number of pages7
JournalEnvironmental Science & Technology
Volume54
Issue number22
DOIs
Publication statusPublished - 17 Nov 2020
Externally publishedYes

ASJC Scopus subject areas

  • General Chemistry
  • Environmental Chemistry

Fingerprint

Dive into the research topics of 'PH-Independent Production of Hydroxyl Radical from Atomic H*-Mediated Electrocatalytic H2O2Reduction: A Green Fenton Process without Byproducts'. Together they form a unique fingerprint.

Cite this