The environmental nanogeosciences involve the study of environmental materials (such as soil, water-solid interfaces, organic and inorganic particles) and nano scale processes that affect chemical reactivity, mobility, and availability to biota. These material can be derived from naturally occuring processes or from anthrophogenic acitivities (e.g. engineered nanomaterials, incidentially produced from human activities).
The Hsu-Kim group is actively involved in the study of the environmental implications of naturally occuring and anthropogenic nanomaterials. Our group has studied the major processes that influence the fate of metal and mineral-based nanomaterials. This work has involved a variety of materials, including metallic silver, zinc oxide, cerium dioxide, and metal sulfides. An overarching theme of this work is that reactivity of the materials (e.g. surface composition, dissolution, redox chemistry, bioavailability) can be linked to fundamental concepts of metal speciation. Much of our work has investigated the interactions between the nanoparticles and natural organic matter (NOM), with special focus on ligand functional groups that may be controlling sorption of NOM to these nanomaterials, and subsequently aggregation, deposition and solubility of the nanoparticles.
We closely collaborate with other researchers who are part of the Center for Environmental Implications of NanoTechnology (CEINT), headquartered at Duke.
Effects of nanoparticles on aquatic passive samplers: ES&T (2015)
Geitner, N.; Cooper, J.; Avellan, A.; Castellon, B.; Perrotta, B.; Bossa, N.; Simonin, M.; Anderson, S.; Inoue, S.; Hochella, M.; Richardson, C.; Bernhardt, E.; Lowry, G.; Ferguson, P.L.; Matson, C.; King, R.; Unrine, J.; Wiesner, M.R.; Hsu-Kim, H. (2018). Size-Based Differential Transport, Uptake, and Mass Distribution of Ceria (CeO2) Nanoparticles in Wetland Mesocosms. Environ. Sci. & Technol. 52, 9768-9776. DOI: 10.1021/acs.est.8b02040
Jiang, C.; Castellon, B.T.; Matson, C.W.; Aiken, G.R.; Hsu-Kim, H. (2017). Relative contributions of copper oxide nanoparticles and dissolved copper to Cu uptake kinetics of Gulf killifish (Fundulus grandis) embryos. Environ. Sci. & Technol. 51, 1395-1404 . DOI:10.1021/acs.est.6b04672
Jiang, C.; Aiken, G.R.; Hsu-Kim, H. (2015). Effects of Natural Organic Matter Properties on the Dissolution Kinetics of Zinc Oxide Nanoparticles. Environ. Sci. & Technol. 49(19), 11476-11484. DOI: 10.1021/acs.est.5b02406
Pham, A. L.-T.; Morris, A., Zhang, T., Ticknor, J.; Levard, C.; Hsu-Kim, H. (2014). Precipitation of Nanoscale Mercuric Sulfides in the Presence of Natural Organic Matter: Structural Properties, Aggregation, and Biotransformation. Geochim. Cosmochim. Acta. 133, 204-215. DOI: 10.1016/j.gca.2014.02.027.
Zhang, T.; Kucharzyk, K.H.; Kim, B.; Deshusses, M.A.; Hsu-Kim, H. (2014). Net methylation of mercury in estuarine sediment microcosms amended with dissolved, nanoparticulate, and microparticulate mercuric sulfides. Environ. Sci. & Technol. 16, 9133-9141. DOI: 10.1021/es500336j.
Aiken G.R., Hsu-Kim H., Ryan J.N. (2011). Influence of dissolved organic matter for the environmental fate of metals, nanoparticles, and colloids. Envir. Sci & Technol. 45, 3196–3201. [publication]
This research is funded by the National Science Foundation, the National Institute for Environmental Health Sciences, and the Center for the Environmental Implications of NanoTechnology (CEINT).