10.1021/acs.est.9b07840.s001
Benedikt Steinhoff
Benedikt
Steinhoff
Julian Müller
Julian
Müller
Darya Mozhayeva
Darya
Mozhayeva
Bastian T. F. Spelz
Bastian T. F.
Spelz
Carsten Engelhard
Carsten
Engelhard
Benjamin Butz
Benjamin
Butz
Holger Schönherr
Holger
Schönherr
Investigation
of the Fate of Silver and Titanium Dioxide
Nanoparticles in Model Wastewater Effluents via Selected Area Electron
Diffraction
American Chemical Society
2020
titanium dioxide nanoparticles
Model Wastewater Effluents
ratio
energy-dispersive X-ray analysis
physicochemical transformation proc...
area electron diffraction
Ag 2 S-NPs
investigation
MNM
Ag 2 S
Selected Area Electron Diffraction
cloud point extraction
WWTP
EDX
SAED
TiO 2
Titanium Dioxide Nanoparticles
Ag-NP
crystal structure analysis
wastewater treatment plants
nanomaterial
2020-06-30 11:41:30
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Investigation_of_the_Fate_of_Silver_and_Titanium_Dioxide_Nanoparticles_in_Model_Wastewater_Effluents_via_Selected_Area_Electron_Diffraction/12588197
The
increasing use of manufactured nanomaterials (MNMs) and their
inevitable release into the environment, especially via wastewater
treatment plants (WWTPs), poses a potential threat for aquatic organisms.
The characterization of MNMs with analytical tools to comprehend their
fate and effect on the ecosystem is hence of great importance for
environmental risk assessment. We herein report, for the first time,
the investigation of physicochemical transformation processes during
artificial wastewater treatment of silver (Ag-NPs) and titanium dioxide
nanoparticles (TiO<sub>2</sub>-NPs) via selected area electron diffraction
(SAED). TiO<sub>2</sub>-NPs with an anatase/rutile ratio of ∼80/20
were found to not undergo any physicochemical transformation, as shown
via previous energy-dispersive X-ray analysis (EDX) elemental mapping
and crystal structure analysis via SAED. In contrast, Ag-NPs were
colocalized with substantial amounts of sulfur (Ag/S ratio of 1.9),
indicating the formation of Ag<sub>2</sub>S. SAED ultimately proved
the complete transformation of face-centered cubic (fcc) Ag-NPs into
monoclinic Ag<sub>2</sub>S-NPs. The size distribution of both nanomaterials
remained virtually unchanged. Our investigations show that cloud point
extraction of NPs and their subsequent crystal structure analysis
via SAED is another valuable approach toward the comprehensive investigation
of wastewater-borne MNMs. However, the extraction procedure needs
optimization for environmentally low NP concentrations.