CAREER: Mineral growth by nanoparticle aggregation: Aluminosilicate minerals

这个CAREER项目的目标是在纳米颗粒聚集的矿物生长科学的前沿发展一个创新的研究项目。铝硅酸盐矿物在自然界中丰富，是土壤和沉积物中最活跃的无机成分之一。纳米硅铝酸盐，如铁长石、allophane和高岭石，以及相关的粘土矿物，如高岭石，由于与水、营养物质（如磷、氮和碳）、重金属污染物和病原体的相互作用，影响土壤的物理和化学性质。了解铝硅酸盐矿物如何在环境条件下形成将导致新的和改进的策略，以提高土壤肥力和预测污染物的运输和命运。对铝硅酸盐生长过程的新见解将导致新的合成方法，用于新的地球丰富的金属催化剂，以及用于水处理应用和长期核废料储存的工程材料。具有明确的特征形状（管状、空心球体、板状等）的硅酸铝纳米颗粒是碳基纳米颗粒的有趣替代品，可用于药物输送和功能复合材料等医疗应用。该项目将通过综合的本科和研究生教学、科学出版物和演讲（包括短期课程和会议专题讨论会）、一般推广和学生研究培训计划，分发和传播新颖的研究方法和成果，从而推动更广泛的科学和技术界。这项工作将使用新的工具和技术来理解结晶科学，包括硅晶体结构可视化和桌面3D打印。这些工具将作为本科和研究生教育课程的一部分，并将在一个新的结晶知识和发现网站上免费提供给其他人。本CAREER项目的主要研究目标是了解纳米级铝硅酸盐矿物如何在低温条件下通过前驱体纳米颗粒的聚集和组装形成。这将通过三个阶段的方法来实现，包括新的系统合成方法和一套互补的同步加速器和实验室方法的表征，使用定制微流体设备的实时结晶研究，以及过程建模。高分辨率电子显微镜结合使用示踪元素作为化学标签的新合成策略将用于跟踪纳米颗粒前体在经典和非经典生长过程中的演变。矿物生长的实时研究将使用最先进的散射和光谱方法，以及由桌面3D打印制造的定制微流体设备。互补分析表征方法的实验结果将与理论和计算相结合，以产生铝硅酸盐纳米颗粒和铝硅酸盐矿物前体的结构和物理化学特征的分子尺度模型。这将导致聚合和前体附着过程的新概念模型。这项关于铝硅酸盐的研究所产生的基本知识将有助于我们了解自然界中的粘土形成，并将为继续研究导致矿物形成的过程提供基础。

The goal of this CAREER project is to develop an innovative research program at the forefront of the science of nanoparticle aggregation-based mineral growth. Aluminosilicate minerals are abundant in nature and among the most reactive inorganic constituents in soils and sediments. Nanosized aluminosilicates such as imogolite, allophane and halloysite, along with related clay minerals such as kaolinite, affect the physical and chemical properties of soils due to interactions with water, nutrients (e.g., Phosphorus, Nitrogen and Carbon), heavy metal contaminants, and pathogens. Learning how aluminosilicate minerals form at environmental conditions will lead to new and improved strategies to enhance soil fertility and to predict pollutant transport and fate. New insights into aluminosilicate growth processes will lead to novel synthesis methods for new earth-abundant metal catalysts, as well as engineered materials for water treatment applications and long-term nuclear waste storage. Aluminosilicate nanoparticles with well-defined characteristic shapes (tubes, hollow spheres, plates, etc.) are an intriguing alternative to carbon-based nanoparticles for medical applications such as drug delivery and functional composite materials. This project will advance the broader scientific and technological community by distributing and disseminating novel research methods and results through an integrated program of undergraduate and graduate teaching, scientific publications and presentations (including short courses and conference symposia), general outreach, and student research training. This effort will use new tools and techniques to understand crystallization science, including in silico crystal structure visualization and desktop 3D printing. These tools will be applied as part of educational curriculum for undergraduate and graduate coursework, and will be available to others at no cost on a new crystallization knowledge and discovery website.The primary research objective of this CAREER project is to understand how nanosized aluminosilicate minerals form at low-temperature conditions via the aggregation and assembly of precursor nanoparticles. This will be achieved using a three-phase approach that includes new systematic synthesis methods and characterization by a suite of complementary synchrotron and laboratory methods, real time crystallization studies using custom microfluidics devices, and process modeling. High-resolution electron microscopy combined with new synthesis strategies using tracer elements as chemical labels will be used to track how nanoparticle precursors evolve during classical and nonclassical growth. Real-time studies of mineral growth will use state-of-the-art scattering and spectroscopic methods along with custom microfluidics devices fabricated by desktop 3D printing. Experimental results from complementary analytical characterization methods will be combined with theory and computation to produce molecular-scale models of structural and physicochemical characteristics of the aluminosilicate nanoparticles and precursors of aluminosilicate minerals. This will lead to new conceptual models for the processes of aggregation and precursor attachment. The fundamental knowledge generated by this research on aluminosilicates will help us understand clay formation in nature, and will provide the foundation for continuing research on processes that lead to mineral formation.