2021/10/12 by Daniel José Pochapski, Caio Carvalho dos Santos, Gabriel Wosiak +2 · 3 citations
Chemistry · Engineering · #Electrokinetic Soil Remediation Techniques #Electrostatics and Colloid Interactions #Nanopore and Nanochannel Transport Studies
paper · doi:10.1021/acs.langmuir.1c02056
openalex publication_date 2021/10/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
In this work, a set of experimental electrophoretic mobility (μ e ) data was used to show how inappropriate selection of the electrokinetic model used to calculate the zeta potential (ζ-potential) can compromise the interpretation of the results for nanoparticles (NPs). The main consequences of using ζ-potential values as criteria to indicate the colloidal stability of NP dispersions are discussed based on DLVO interaction energy predictions. For this, magnetite (Fe 3 O 4 ) NPs were synthesized and characterized as a model system for performing electrokinetic experiments. The results showed that the Fe 3 O 4 NPs formed mass fractal aggregates in solution, so the ζ-potential could not be determined under ideal conditions when μ e depends on the NP radius. In addition, the Dukhin number (Du) estimated from potentiometric titration results indicated that stagnant layer conduction (SLC) could not be neglected for this system. The electrokinetic models that do not consider SLC grossly underestimated the ζ-potential values for the Fe 3 O 4 NPs. The DLVO interaction energy predictions for the colloidal stability of the Fe 3 O 4 NP dispersions also depended on the electrokinetic model used to calculate the ζ-potential. The results obtained for the Fe 3 O 4 NP dispersions also suggested that, contrary to many reports in the literature, high ζ-potential values do not necessarily reflect high colloidal stability for charge-stabilized NP dispersions.