TY - JOUR
T1 - Transport of Single-Layered Graphene Oxide Nanosheets through Quartz and Iron Oxide-Coated Sand Columns
AU - Duster, Thomas A.
AU - Na, Chongzheng
AU - Bolster, Diogo
AU - Fein, Jeremy B.
N1 - Funding Information:
This research was supported, in part, by fellowships to the first author from the Arthur J. Schmitt Foundation and the National Research Council. In addition, the authors performed most experiments and analyses using instrumentation at the Center for Environmental Science and Technology (University of Notre Dame). The authors also acknowledge a substantial technical contribution by Jennifer Szymanowski (ND) and additional research guidance by Dr. Lauren Greenlee (NIST). The second authors contribution was supported by the USDOE Office of Nuclear Energys Nuclear Energy University Programs, the U.S. National Science Foundations Environmental Engineering Program, the donors of the ACS Petroleum Research Fund, and the University of Notre Dame Sustainable Energy Initiative. Contribution of the National Institute of Standards and Technology, an agency of the United States government; not subject to copyright in the United States. Certain commercial equipment, instruments, databases, or materials may be identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
Publisher Copyright:
© 2016 American Society of Civil Engineers.
PY - 2017/2/1
Y1 - 2017/2/1
N2 - Single-layered graphene oxide (SLGO) nanosheets are distinguished from other colloids by their extreme anisotropy, which likely exerts a strong control on their transport behavior. Hence, this study investigates the influence of both environmentally relevant pH and ionic strength on the transport of SLGO nanosheets through saturated quartz or iron oxide-coated sands. Both the nanosheets and quartz sands are negatively charged throughout the experimental conditions, resulting in very little nanosheet deposition onto the quartz sands. However, increasing ionic strength and decreasing pH did cause measurable increases in nanosheet deposition, likely due to decreases in the magnitude of negative charges near the respective surfaces. Conversely, nanosheets and iron oxide-coated sands are oppositely charged throughout the experimental conditions, resulting in significant nanosheet deposition onto the iron oxide-coated sands. These trends suggest that nanosheet deposition is largely controlled by electrostatic forces, although the deposition rate of the high ionic strength iron oxide-coated sand treatment could not be explained by electrostatic interactions alone and instead may be influenced by nanosheet aggregation. Collectively, these measurements enable prediction of SLGO transport throughout a range of realistic environmental and geologic conditions.
AB - Single-layered graphene oxide (SLGO) nanosheets are distinguished from other colloids by their extreme anisotropy, which likely exerts a strong control on their transport behavior. Hence, this study investigates the influence of both environmentally relevant pH and ionic strength on the transport of SLGO nanosheets through saturated quartz or iron oxide-coated sands. Both the nanosheets and quartz sands are negatively charged throughout the experimental conditions, resulting in very little nanosheet deposition onto the quartz sands. However, increasing ionic strength and decreasing pH did cause measurable increases in nanosheet deposition, likely due to decreases in the magnitude of negative charges near the respective surfaces. Conversely, nanosheets and iron oxide-coated sands are oppositely charged throughout the experimental conditions, resulting in significant nanosheet deposition onto the iron oxide-coated sands. These trends suggest that nanosheet deposition is largely controlled by electrostatic forces, although the deposition rate of the high ionic strength iron oxide-coated sand treatment could not be explained by electrostatic interactions alone and instead may be influenced by nanosheet aggregation. Collectively, these measurements enable prediction of SLGO transport throughout a range of realistic environmental and geologic conditions.
KW - Deposition rate
KW - Iron oxide
KW - Quartz
KW - Single-layered graphene oxide (SLGO)
KW - Transport
UR - http://www.scopus.com/inward/record.url?scp=85026636272&partnerID=8YFLogxK
U2 - 10.1061/(ASCE)EE.1943-7870.0001156
DO - 10.1061/(ASCE)EE.1943-7870.0001156
M3 - Article
AN - SCOPUS:85026636272
VL - 143
JO - Journal of Environmental Engineering
JF - Journal of Environmental Engineering
SN - 0733-9372
IS - 2
M1 - 04016079
ER -