Probing Iron Oxide Mineral Aggregation Behavior with Soil Organic Matters
EMSL Project ID
51382
Abstract
The goal of this project is to develop a fundamental understanding of iron oxide nanoparticle (NPs) aggregation mechanisms with soil organic matters (SOM). Heteroaggregation is a ubiquitous but poorly understood phenomenon that strongly impacts iron bioavailability and carbon protection in soils1. As is the case for most NPs in the environment, this tendency to form larger complex multiphase aggregates that couples the fates of its constituent particles is well established.2-4 However, to date, only in environmentally unrealistic single-phase systems of uniform spherical particles can aggregation behavior be reliably predicted as a function of pH, electrolyte type and ionic strength. Beyond this case, theories of net interparticle forces such as extended-DLVO continue to be useless given their over-simplified description of particle sizes, shapes, and physical interactions5. Furthermore, the effects of complex organics such as SOM, which adds complexity in molecular structure, hydrophobic forces, and a variety of reactive functional groups are well beyond the reach of any present day predictive aggregation models.Previous EMSL-supported research (Proposals 48274 and 49383) by our team led to the development of a novel single nanocrystal AFM probe fabrication technique via using the focused ion beam (FIB)-scanning electron microscopy (SEM) capability. This allowed us to explore in detail, for the first time, the underlying forces in oriented aggregation, including the effects of intervening adsorbed water layers6 and electrolyte ions7. This included first-ever visualization and quantification of particle interaction forces at the nanoscale using the unique in situ environmental transmission electron microscopy (ETEM)-atomic force microscopy (AFM) technique6 (Fig. 1A) in EMSL. And using AFM-based dynamic force spectroscopy (DFS) coupled with high-performance computing simulations, this preliminary work also showed the importance of the self-organization of water molecules between NPs which supplies a rotational force that aligns incoming particles into oriented aggregates7 (Fig. 1B).
The proposed new research will capitalize on team momentum with these key EMSL capabilities and focus on hematite NPs to unravel (i) the facet dependence of the interaction force with SOM; and (ii) the effect of SOM on the interaction forces between hematite NPs. Specifically, we will combine time-of-flight secondary ion mass spectrometry (ToF-SIMS), AFM, and high-performance computing to quantify and understand interaction forces with SOM, adding spectroscopic techniques of XPS and EPR to interrogate the structure and characteristics of these interfacial organics. Advanced one-of-a-kind theory and simulation will provide a basis for quantifying the energetics and kinetics of SOM bonding on hematite nano-minerals with different facets. We will leverage unique knowledge and skills gained from the previous cycle of EMSL-supported research in exploiting FIB-SEM, S/TEM and AFM.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2020-10-01
End Date
2022-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members
Related Publications
Anne M. Chaka, James J. De Yoreo, Alan S. Lea, John S. Loring, Sebastian T. Mergelsberg, Elias Nakouzi, Odeta Qafoku, Kevin M. Rosso, Herbert T. Schaef, Xin Zhang. 2021. "In situ imaging of amorphous intermediates during brucite carbonation in supercritical CO2." Nature Materials 21 (3):345-351. 10.1038/s41563-021-01154-5
James J. De Yoreo, Yang He, Qingyun Lin, Lili Liu, Kevin M. Rosso, Duo Song, Maria L. Sushko, Yining Wang, Sichuang Xue, Xin Zhang, Jianbin Zhou, Junwu Zhu, Meirong Zong. 2022. "Particle-based hematite crystallization is invariant to initial particle morphology." Proceedings of the National Academy of Sciences 119 (11) 10.1073/pnas.2112679119
Ping Chen, Tianhu Chen, Haibo Liu, Kevin M. Rosso, Duo Song, Qiaoqin Xie, Liang Xu, Xin Zhang, Yuefei Zhou. 2022. "Understanding Competitive Phosphate and Silicate Adsorption on Goethite by Connecting Batch Experiments with Density Functional Theory Calculations." Environmental Science & Technology 56 (2):823-834. 10.1021/acs.est.1c03629
Xiaopeng Huang, Xiancai Lu, Kevin M. Rosso, Duo Song, Xin Zhang, Meirong Zong. 2020. "Facet-Dependent Photodegradation of Methylene Blue by Hematite Nanoplates in Visible Light." Environmental Science & Technology 55 (1):677-688. 10.1021/acs.est.0c05592