2026-06-29T08:21:17Zhttps://docta.ucm.es/rest/oai/requestoai:docta.ucm.es:20.500.14352/1265102025-11-26T00:53:13Zcom_20.500.14352_14col_20.500.14352_15
Real-time Cr(VI) monitoring and remediation using Fe3O4 nanoparticles: Insights into Fe-Cr Spinels
Martínez Boubeta, Carlos
Balcells, Luis
Beltrán Fínez, Juan Ignacio
Martínez Peña, G. I.
Virgiliou, C.
Kalaitzidou, K.
Vourlias, G.
Teran, F. J.
Salutari, F.
Spadaro, M. Chiara
Arbiol, J.
Simeonidis, K.
538.9
544
Drinking water monitoring
Pollutant sensors
Hexavalent chromium
Magnetite nanoparticles
Magnetic anisotropy
AC magnetometry
DFT calculations
XPS analysis
Física de materiales
Agua
Física (Química)
2210 Química Física
© 2025 The Authors.
PTQ2021-012178
An analytical approach for the rapid and remote determination of Cr(VI) in water samples is demonstrated using Fe3O4 nanoparticles and a cost-effective portable AC magnetometer. Cr(VI) reduction by surface Fe²⁺ leads to Fe/Cr precipitate formation, which alters the nanoparticles’ magnetic properties. Validation in natural water spiked with Cr(VI) showed a linear correlation between magnetic remanence and Cr(VI) concentrations from 0 to 10 mg/L, with a R2 value of 0.99. Limitations of the method emerged at loadings above 10 mg/g, where extensive chromite (CrxFe3-xO4) coverage reduced the magnetic hysteresis area. Advanced characterization and DFT calculations revealed changes in spin-dependent properties, including magnetization reversal, electrical conductivity and magnetoresistance. This robust correlation between collective magnetic properties and Cr(VI) exposure enables, for the first time, milligram-per-liter detection via ultra-fast AC magnetometry, paving the way for real-time insight into redox processes in liquid environments and novel strategies for environmental remediation.
Minisiterio de Ciencia e Innovación (España)
Agencia Estatal de Investigación (España)
European Commission
Nanotech Solutions S.L.
Hellenic Foundation for Research and Innovation
Generalitat de Catalunya
Depto. de Física de Materiales
Fac. de Ciencias Físicas
TRUE
pub
2025-11-25T15:35:22Z
2025-11-25T15:35:22Z
2025-08-20
journal article
VoR
https://hdl.handle.net/20.500.14352/126510
2214-7144
10.1016/j.jwpe.2025.108496
eng
00046.
info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2021-2023/PID2021-122980OB-C51/ES/ESTUDIOS DE FENOMENOS ATOMISTICOS EN MATERIALES MULTIFUNCIONALES A TRAVES DE TECNICAS IN-SITU/
2021SGR00457
info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2021-2023/CEX2021-001214-S
C. Martinez-Boubeta, Ll. Balcells, J.I.B. Finez, G.I. Martinez-Peña, C. Virgiliou, K. Kalaitzidou, G. Vourlias, F.J. Teran, F. Salutari, M.C. Spadaro, J. Arbiol, K. Simeonidis, Real-time Cr(VI) monitoring and remediation using Fe3O4 nanoparticles: Insights into Fe-Cr Spinels, Journal of Water Process Engineering 77 (2025) 108496. https://doi.org/10.1016/j.jwpe.2025.108496.
Attribution 4.0 International
http://creativecommons.org/licenses/by/4.0/
open access
application/pdf
application/pdf
Elsevier