Stability of uncoated and fulvic acids coated manufactured CeO2 nanoparticles in various conditions: From ultrapure to natural Lake Geneva waters.
Understanding the behavior of engineered nanoparticles in natural water and impact of water composition in changing conditions is of high importance to predict their fate once released into the environment. In this study we investigated the stability of uncoated and Suwannee River fulvic acids coated CeO2 manufactured nanoparticles in various environmental conditions. The effect of pH changes on the nanoparticle and coating stability was first studied in ultrapure water as well as the variation of zeta potentials and sizes with time in presence of fulvic acids at environmental pH. Then the stability of CeO2 in synthetic and natural Lake Geneva waters was investigated as a function of fulvic acids concentration. Our results indicate that the adsorption of environmentally relevant concentrations of Suwannee River fulvic acids promotes CeO2 stabilization in ultrapure water as well as synthetic water and that the coating stability is high upon pH variations. On the other hand in natural Lake Geneva water CeO2 NPs are found in all cases aggregated due to the effect of heterogeneous organic and inorganic compounds.
Institute F.-A. Forel, University of Geneva, Faculty of Science, Uni Carl Vogt, Group of Environmental Physical Chemistry, 66, Boulevard Carl-Vogt, CH 1211 Geneva, 4, Switzerland. Electronic address: Olena.Oriekhova@unige.ch.
Olena
O
Oriekhova
Institute F.-A. Forel, University of Geneva, Faculty of Science, Uni Carl Vogt, Group of Environmental Physical Chemistry, 66, Boulevard Carl-Vogt, CH 1211 Geneva, 4, Switzerland. Electronic address: Serge.Stoll@unige.ch.
Serge
S
Stoll
D001578:Benzopyrans / Q000737:chemistry*; D002563:Cerium / Q000032:analysis* / Q000737:chemistry; D004784:Environmental Monitoring; D060106:Lakes / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000032:analysis* / Q000737:chemistry; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry; D013557:Switzerland
D001578:Benzopyrans; D002563:Cerium; C030583:ceric oxide; C005023:fulvic acid
Aggregation; CeO(2) nanoparticle stability; Complexation; Fulvic acids coating; Surface charge modification