CEE Seminar: Biogeochemistry of Engineered Nanomaterials in Natural Waters

Abstract: Nanotechnology, the manipulation of matter at the nanoscale, can contribute to environmental sustainability via applications that can improve energy storage, water treatment and pollution remediation, among others. However, nanotechnology applications may lead to release of engineered nanomaterials (ENMs) into the natural environment, and the implications of this exposure are poorly understood. The fate of ENMs in the environment is primarily controlled by the intrinsic physicochemical properties of the particles, such as elemental composition, particle size, crystallinity and surface charge. The interactions between ENMs and biogeochemical factors in the environment − such as water chemistry, natural organic matter and microorganisms − may also play important roles in the environmental fate and transformation of ENMs. The first part of this seminar will focus on the role of water chemistry on the release and speciation of Cu from surfaces coated with a Cu₂O-based antifouling paint, and the fate and effects of Cu₂O nanoparticles in aquatic environments. Environmental feedback between microorganisms and the ENMs will be discussed to highlight the role of biology in the reactivity and speciation of the Cu₂O nanoparticles, and how that, in turn, influences the impact of ENMs on the biochemical processes of the microorganisms. The second part of this seminar will focus on the application of nanoscale zerovalent iron (nZVI) for heavy metal removal, showing how the ENM can be modified to improve its performance. The influence of biogeochemical parameters on the transformation and toxic effects of nZVI will be considered, with the goal of improving the sustainable application of nZVI for environmental remediation.

Bio: Adeyemi Adeleye is a recipient of the Research Associateship Program fellowship from the National Research Council (NRC), and is currently a NRC postdoctoral research associate at the U.S. Environmental Protection Agency. He is a native of Nigeria, where he obtained a B.S. (first class honors) in microbiology from Obafemi Awolowo University, Ile-Ife. He then earned a master's degree (2011) and a Ph.D. (2015) in environmental science & management at the University of California, Santa Barbara. Adeleye’s research focuses on environmental applications and implications of nanotechnology. He is interested in using engineered nanoparticles to improve water quality while also understanding the fate and transformation of engineered nanomaterials and other emerging contaminants in the natural environment. He previously worked as a postdoctoral scholar at the University of California’s Center for Environmental Implications of Nanotechnology (UCCEIN) at UCSB.