Issue 7, 2023

Electrospun TiO2/carbon composite nanofibers as effective (photo)electrodes for removal and transformation of recalcitrant water contaminants

Abstract

Electrochemical (EC) and photoelectrochemical (PEC) water treatment systems are gaining popularity, necessitating new electrode materials that offer reliable performance across diverse application platforms. For applications specifically targeting dilute chemical pollutants (i.e., parts-per-million concentrations or less), beneficial electrode properties include high surface area to overcome kinetic overpotential losses, low electrode areal electrical resistance, and high water permeability with sufficient mechanical strength for use in electroactive membrane-based treatment systems. Here, we used electrospinning to fabricate (photo)electrodes from carbon nanofibers (CNFs) containing titanium dioxide (TiO2) nanoparticles. Optimal CNF/TiO2 composites were electrochemically and photochemically active with a surface area of ∼50 m2 g−1 and electrode areal resistance of 2.66 Ω cm2, values comparable to commercial carbon-based electrode materials (e.g., Kynol Activated Carbon Cloth). Transformation experiments with carbamazepine (CBZ), a recalcitrant organic contaminant, suggest CNF/TiO2 electrodes function dually as sorbents, first binding CBZ prior to oxidation at positive applied potentials. Complete CBZ transformation was observed in both EC (dark) and PEC (UV light; 280 mW cm−2) systems over 90 minutes, with PEC systems exhibiting 1.5-fold higher transformation rates (kobs ∼ 0.18 min−1) at +1.00 V (vs. Ag/AgCl). Composite electrodes also exhibited stability across repeated use, yielding consistent current densities over five experimental cycles (120 min each) of CBZ transformation (0.25 ± 0.03 mA cm−2). Because of their high surface area, electrical conductivity, photoactivity, and electrochemical stability, these electrospun CNF/TiO2 composites represent promising (photo)electrode alternatives for diverse EC and PEC applications.

Graphical abstract: Electrospun TiO2/carbon composite nanofibers as effective (photo)electrodes for removal and transformation of recalcitrant water contaminants

Supplementary files

Article information

Article type
Paper
Submitted
24 janv. 2023
Accepted
03 mai 2023
First published
04 mai 2023
This article is Open Access
Creative Commons BY-NC license

Environ. Sci.: Adv., 2023,2, 967-981

Electrospun TiO2/carbon composite nanofibers as effective (photo)electrodes for removal and transformation of recalcitrant water contaminants

A. H. Butzlaff, M. Jensen, C. Yan, A. Ghanim, C. Werth, D. Cwiertny and S. Mubeen, Environ. Sci.: Adv., 2023, 2, 967 DOI: 10.1039/D3VA00017F

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements