In this section
@article{Bullen:2022:10.1002/chem.202104181,
author = {Bullen, JC and Heiba, HF and Kafizas, A and Weiss, DJ},
doi = {10.1002/chem.202104181},
journal = {Chemistry: A European Journal},
title = {Parasitic light absorption, rate laws and heterojunctions in the photocatalytic oxidation of arsenic(III) using composite TiO2/Fe2O3},
url = {http://dx.doi.org/10.1002/chem.202104181},
volume = {28},
year = {2022}
}
TY - JOUR
AB - Composite photocatalyst-adsorbents such as TiO2/Fe2O3 are promising materials for the one-step treatment of arsenite contaminated water. However, no previous study has investigated how coupling TiO2 with Fe2O3 influences the photocatalytic oxidation of arsenic(III). Herein, we develop new hybrid experiment/modelling approaches to study light absorption, charge carrier behaviour and changes in the rate law of the TiO2/Fe2O3 system, using UV-Vis spectroscopy, transient absorption spectroscopy (TAS), and kinetic analysis. Whilst coupling TiO2 with Fe2O3 improves total arsenic removal by adsorption, oxidation rates significantly decrease (up to a factor of 60), primarily due to the parasitic absorption of light by Fe2O3 (88% of photons at 368 nm) and secondly due to changes in the rate law from disguised zero-order kinetics to first-order kinetics. Charge transfer across this TiO2-Fe2O3 heterojunction is not observed. Our study demonstrates the first application of a multi-adsorbate surface complexation model (SCM) towards describing As(III) oxidation kinetics which, unlike Langmuir-Hinshelwood kinetics, includes the competitive adsorption of As(V), and we further highlight the importance of parasitic light absorption and catalyst fouling when designing heterogeneous photocatalysts for As(III) remediation.
AU - Bullen,JC
AU - Heiba,HF
AU - Kafizas,A
AU - Weiss,DJ
DO - 10.1002/chem.202104181
PY - 2022///
SN - 0947-6539
TI - Parasitic light absorption, rate laws and heterojunctions in the photocatalytic oxidation of arsenic(III) using composite TiO2/Fe2O3
T2 - Chemistry: A European Journal
UR - http://dx.doi.org/10.1002/chem.202104181
UR - https://www.ncbi.nlm.nih.gov/pubmed/35114042
UR - https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202104181
UR - http://hdl.handle.net/10044/1/95124
VL - 28
ER -
Dr. Andreas Kafizas
Leader - Solar Coatings Group
e-mail: a.kafizas@imperial.ac.uk
tel: +44(0)20 7594 6752
twitter: @CoatingsSolar