BRIGE: Sustainable Methods for the Production of Anisotropic Metallic Nanoparticles Using Tunable Fluids

该bridge奖支持气体膨胀液体（GXLs）作为生产各向异性金属纳米颗粒的新型加工介质的研究；它们显示独特的依赖于形态的属性。研究目标是：1)利用胶体定向组装在gxl中合成各向异性纳米颗粒；2)展示利用gxl快速分离各向异性纳米颗粒并沉积成均匀有序阵列的有效方法；3)对控制gxl中各向异性纳米颗粒合成和加工的粒子间相互作用和表面力有基本的了解。之前的工作已经研究了使用GXLs（二氧化碳和有机溶剂的低压混合物）和其他可调流体来合成和处理配体稳定的球形金属纳米颗粒。在这里，可调流体，特别是gxl，将为各种应用的独特纳米材料的生产提供可持续的手段。gxl中的金和银纳米棒将通过发展种子介导的生长过程来产生；再加上GXL介导的加工，以产生均匀的纳米棒种群和远程有序的纳米棒阵列。先进的表征技术和热力学建模将被用来获得对各向异性纳米颗粒合成和定向组装的基本理解，以进一步提高生产和加工能力。如果成功，这项工作将推进纳米材料合成和制造领域的知识，通过宣传两个具体的理念：1)可持续的纳米颗粒合成和加工方法是可以实现的，并且在大规模、经济和绿色纳米材料生产方面具有比传统方法显著的优势。2)各向异性纳米颗粒合成的基本驱动力是由定向组装而不是传统的胶体模板机制产生的动力学控制过程。

This BRIGE award supports the study of gas expanded liquids (GXLs) as a novel processing media for the production of anisotropic, metallic nanoparticles; which display unique morphology-dependent properties. The research objectives are to 1) synthesize anisotropic nanoparticles using colloidal directed assembly within GXLs, 2) demonstrate effective methods for the rapid size-fractionation of anisotropic nanoparticles and deposition into uniform, ordered arrays using GXLs, and 3) gain a fundamental understanding of the interparticle interactions and surface forces that govern the synthesis and processing of anisotropic nanoparticles in GXLs. Previous work has investigated the use of GXLs (low-pressure mixtures of CO2 and organic solvents) and other tunable fluids for the synthesis and processing of ligand-stabilized, spherical metallic nanoparticles. Here tunable fluids, specifically GXLs, will provide sustainable means for the production of unique nanomaterials for diverse applications. Gold and silver nanorods in GXLs will be produced by developing a seed-mediated growth processes; coupled with GXL mediated processing to yield uniform nanorod populations and long-range, ordered nanorod arrays. Advanced characterization techniques and thermodynamic modeling will be employed to gain a fundamental understanding of the anisotropic nanoparticle synthesis and directed assembly to further enhance production and processing capabilities.If successful, this work will advance knowledge in the field of nanomaterial synthesis and manufacture by campaigning two specific philosophies: 1) Sustainable methods of nanoparticle synthesis and processing are achievable and have significant advantages over conventional methodologies for large-scale, economic, and green nanomaterial production. 2) The fundamental driving force for the synthesis of anisotropic nanoparticles is kinetically controlled processes that result from directed assembly rather than conventional colloidal template mechanisms.