Explore the Nano World
Wen's Research Group
Wen Zhang, Ph.D., P.E., BCEE
Principal Investigator
Professor
Phone: (973) 596-5520
Fax: (973) 596-5790
Email: wen.zhang@njit.edu
Office Location: Colton Hall 211
Find us on the map:
Electrochemical Aging and Halogen Oxides Formation on Multiwalled Carbon Nanotubes and Fe3O4@g-C3N4 Coated Conductive Membranes
Dr. Wen Zhang’s group in New Jersey Institute of Technology reported electrochemical membrane aging mechanisms and byproducts formation during membrane filtration. Specifically, this study investigated the membrane aging processes of two types of conductive membranes, multiwalled carbon nanotubes (MWCNTs) and ferrite/graphitic carbon nitride hybrids (Fe3O4@g-C3N4) coated on ceramic membranes. Under high current densities (~20 mA·cm−2) and anodic potentials (~10 V), MWCNTs and Fe3O4@g-C3N4 catalysts underwent evident oxidation as indicated by an increase of the intensity ratio of the Raman spectral bands (ID/IG) and charge transfer resistance (Rct) of two electrochemical membranes. Under variations of electrode potentials, chloride or bromide were shown to be oxidized to bromate (BrO3−) and chlorate (ClO3−) at levels of 1-10 mmol·L−1. The formation of BrO3− and ClO3− was dependent on the solution pH, current densities (1-20 mA·cm−2) and initial concentrations of Br or Cl ions. This study is beneficial to warrant a safe and rational design and operation of electrochemically reactive membrane processes, membrane aging and toxic byproduct’s formation deserve careful characterization under relevant water filtration environments. This research is supported by New Jersey Water Resources Research Institute (NJWRRI) Grant (Project Number: 2020NJ025B), NSF PFI grant (Award number: 2016472), NSF INTERN grant (Award number: 1836036), National Natural Science Foundation of China (52070117) and the United States Environmental Protection Agency (US EPA) P3 Program under Assistance Agreement No. (83945201).