Influence of organic molecules on the aggregation of TiO2 nanoparticles in acidic conditions

• DOI: 10.1007/s11051-017-3807-9
• Publication Date: 2017-04-05T07:24:26Z
• Authors: Karin Danielsson; Julián A. Gallego...; Martin Hassellov; Stefan Gustafsson; Caroline M. Jonsson
• Keywords: Surface charge; Micrometer; Particle (ecology)

Engineered nanoparticles released into the environment may interact with natural organic matter (NOM). Surface complexation affects surface potential, which in turn lead to aggregation of particles. Aggregation synthetic TiO2 (anatase) aqueous suspension was investigated at pH 2.8 as a function time presence various molecules and Suwannee River fulvic acid (SRFA), using dynamic light scattering (DLS) high-resolution transmission electron microscopy (TEM). Results showed that average hydrodynamic diameter ζ-potential were dependent on both concentration molecular structure molecule. also compared those quantitative batch adsorption experiments. Further, study 2,3-dihydroxybenzoic (2,3-DHBA) SRFA, respectively, performed order observe changes particle size over period 9 months. In 2,3-DHBA-TiO2 system, ζ-potentials decreased resulting charge neutralization and/or inversion depending ligand concentration. Aggregate sizes increased initially micrometer range, followed by disaggregation after several No or very little interaction between SRFA occurred lowest concentrations tested. However, higher there an increase aggregate amount adsorbed surface. This correlation concentration, leading destabilization system. These results stress importance performing studies short long periods better understand predict long-term effects environment.