Evaluation of the hydrogenation reaction on the electrocatalytic nitrobenzene degradation over (FeCoNiCuZn)xOy high entropy oxides (HEOs)

Victor Márquez; Mohammad Fereidooni; Janaina S Santos; Supareak Praserthdam; Piyasan Praserthdam

doi:10.1016/j.chemosphere.2023.140130

Evaluation of the hydrogenation reaction on the electrocatalytic nitrobenzene degradation over (FeCoNiCuZn)_xO_y high entropy oxides (HEOs)

Chemosphere. 2023 Nov:341:140130. doi: 10.1016/j.chemosphere.2023.140130. Epub 2023 Sep 8.

Authors

Victor Márquez¹, Mohammad Fereidooni¹, Janaina S Santos¹, Supareak Praserthdam², Piyasan Praserthdam³

Affiliations

¹ Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand.
² Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; High-Performance Computing Unit (CECC-HCU), Center of Excellence on Catalysis and Catalytic Reaction Engineering (CECC), Chulalongkorn University, Bangkok, 10330, Thailand.
³ Center of Excellence on Catalysis and Catalytic Reaction Engineering, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; CAT-REAC Industrial Center, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand. Electronic address: piyasan.p@chula.ac.th.

PMID: 37690554
DOI: 10.1016/j.chemosphere.2023.140130

Abstract

Environmental pollution is one of the main challenges currently faced by mankind; especially industrial waste-waters treatment and remediation using energy-efficient methodologies. This research focused on the electrochemical degradation of the hazardous nitrobenzene (NB) in aqueous solutions, using novel high-entropy oxide (HEO) electrodes to elucidate the influence of the electrochemical reduction step on the degradation process. The effect of solution pH, dissolved oxygen concentration, anodic applied potential, and cell configurations on NB hydrogenation reaction were evaluated. A synergistic effect between the hydrogenation of nitrobenzene and the degradation was found to drastically enhance the conversion rates. The presence of dissolved oxygen promoted the oxidation reactions, reaching more than 90% nitrobenzene removal at 1.7 V and pH 14. The degradation of the organic by-products was attributed to the formation of the superoxide radical (O₂*^-) as the main oxidant species. A degradation mechanism was proposed based on the detected intermediates and the decoupling of electrochemical surface reactions observed by EIS at different solution pH.

Keywords: Electrocatalysis; High entropy oxides (HEOs); Hydrogenation-assisted degradation; Nitrobenzene degradation.

MeSH terms

Entropy
Hydrogenation
Nitrobenzenes*
Oxides*
Oxygen

Substances

Oxides
nitrobenzene
Nitrobenzenes
Oxygen