Collaborative Research: Quantifying the Reactive Surface Area of Environmental Solids

美国国家科学基金会化学部的环境化学科学项目支持来自加州大学默塞德分校的Peggy A. O'Day教授、宾夕法尼亚州立大学和西北太平洋国家实验室的Karl T. Mueller教授以及宾夕法尼亚州立大学的James D. Kubicki教授的研究，他们将进行合作研究，调查环境固体的活性表面及其动态性质。在氧化物和粘土矿物表面吸附二价阳离子的水系统中，竞争吸附、动力学和老化将通过使用固态核磁共振（NMR）光谱结合互补光谱/微观表征和计算化学，开发新的、特定位点的探针分子来研究。这项研究将解决关于环境固体表面的活性分子结合位点及其动态性质的基本问题。矿物表面反应性的精确标度是广泛适用的，对许多重要的社会相关应用至关重要。潜在的更广泛的影响包括，例如，评估与环境污染物有关的风险，如金属、放射性核素和有机污染物的地表和地下迁移或自然衰减；量化过程，如磷、氮和铁被矿物颗粒吸收进入湖泊或海洋的养分输入；估算地下注入过程中矿物对CO2的反应和封存程度。该研究项目将培养跨学科化学环境科学的研究生和博士后学者，涉及多重和迭代光谱表征方法和定量计算方法。

The Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation supports the research of Professors Peggy A. O'Day from the University of California- Merced, Karl T. Mueller from Pennsylvania State University and Pacific Northwest National Laboratory, and James D. Kubicki of Pennsylvania State University who will perform collaborative research that will investigate reactive surfaces of environmental solids and their dynamic nature. Competitive adsorption, kinetics, and aging in aqueous systems of divalent cations sorbed to oxide and clay mineral surfaces will be examined through the development of novel, site-specific probe molecule(s) using solid-state nuclear magnetic resonance (NMR) spectroscopy in conjunction with complementary spectroscopic/microscopic characterizations and computational chemistry. This research will address fundamental, long-standing questions about active, molecular binding sites at surfaces of environmental solids and their dynamic nature.Accurate scaling of mineral surface reactivity is broadly applicable and essential to a number of important applications of societal relevance. Potential broader impacts include, for example, assessing risks associated with environmental contaminants such as surface and subsurface migration or natural attenuation of metal, radionuclide, and organic contaminants; quantifying processes such as nutrient input of P, N, and Fe sorbed on mineral particles into lakes or the oceans; and estimating the extent of CO2 reaction and sequestration by minerals in subsurface injection. This research program will train graduate students and postdoctoral scholars in interdisciplinary chemical environmental sciences involving multiple and iterative spectroscopic characterization methods and quantitative computational approaches.