Carbon Combustion Synthesis in Patterned Precursor Media

LitvinovCarbon燃烧合成微米和纳米结构的复合氧化物似乎提供了一种简单而有效的方法来制造复杂的微米和纳米结构的氧化物，用于生物医学成像、药物输送、数据存储、生物传感器、存储设备、纳米电子学和能量存储。为了响应对这种新材料的需求，人们开发了许多合成方法，这些方法具有不同的复杂性、材料质量、生产成本和效率。然而，通常情况下，相对复杂、高反应物成本和副产品处理的环境问题限制了大规模应用。在碳燃烧合成中，简单氧化物与纳米石墨的化学计量混合粉末在碳的放热氧化作用下的自蔓延反应波中形成纳米颗粒。合成在几秒的时间尺度上进行，热前沿传播速度在0.1至3 mm/S的范围内；关于该工艺的薄膜版本的初步数据显示，转换时间不到1秒。这项技术具有简单、低反应成本和不产生二氧化碳以外的其他副产品的巨大前景。这个实验和模拟项目的目标是深入了解相成核和生长的机制，并应用这些知识来控制材料的性能。这项工作特别具有创新性，因为将首次研究在图案化前驱体介质中的燃烧合成。将开发一个用于实时合成监控和反应产物合成后表征的有效工具集并用于实验。为了解释这些数据，并预测二氧化碳的释放和氧气的反扩散对碳燃烧合成过程中的热能传输和产品性质的影响，将开发一个计算机模型。目标用途是以钴铁氧体为模型体系，高效合成具有精确可控性能的磁性纳米颗粒，应用于生物传感器、数据存储和医学成像。除了潜在的技术影响外，该计划的成果将被整合到国际和平研究所教授的现有材料相关课程中。参与该项目的一批不同的研究生和本科生将走在一个具有广泛工业潜力的迷人科学领域的前沿。

0933140LitvinovCarbon combustion synthesis of micro and nanostructured complex oxides appears to offer a simple and efficient method for making complex micro- and nanostructured oxides to be used in biomedical imaging, drug delivery, data storage, biosensors, memory devices, nanoelectronics, and energy storage. To respond to the demand for such new materials, many synthesis approaches have been developed with varying complexities, materials quality, production costs and efficiency. Often, however, relative complexity, high reactant costs, and environmental issues of by-product disposal limit large-scale applications. In carbon combustion synthesis, nanoparticulates are formed from stoichiometric powder mixtures of simple oxides with nano graphite in a self-propagating reaction wave sustained by exothermic oxidation of carbon. Synthesis occurs on a time scale of several seconds with the thermal front propagation velocities in the range of 0.1 to 3 mm/s; preliminary data on a thin-film version of the process show less than 1sec conversion times. The technology carries a significant promise for simplicity, low reactant costs, and no other byproducts than carbon dioxide.The goal of this experimental and modeling project is to gain insight into the mechanisms of phase nucleation and growth and to apply the knowledge for control of the material properties. The work is particularly innovative in that, for the first time, combustion synthesis in patterned precursor media will be investigated. An efficient toolset for real-time synthesis monitoring and post-synthesis characterization of reaction products will be developed and used for the experiments. To interpret the data and to predict the impacts of carbon dioxide release and the counterdiffusion of oxygen on thermal energy transport during carbon combustion synthesis and on the properties of the products, a computer model will be developed. The target use is efficient synthesis of magnetic nanoparticles with precision-controlled properties for applications in biosensors, data storage, and medical imaging, using cobalt ferrite as a model system. In addition to the potential technological impacts, findings of the program will be integrated into the existing materials-related courses taught by the PI. A diverse set of graduate and undergraduate students participating in the program will be at the forefront of a fascinating scientific field with broad industrial potential.