Nanostructure Synthesis at the Liquid-Substrate Interface: A New Strategy for Obtaining Plasmonic and Chemically Active Surfaces

非技术摘要变革性纳米技术的关键推动因素是纳米材料合成和对指导其形成的化学和物理学的理解方面的突破。应用通常要求纳米材料悬浮在液体中或固定在平面基底上，如玻璃或硅。虽然基于基底的纳米结构合成技术已经无可争议地产生了一系列令人印象深刻的技术相关纳米材料，但这种成功的范围和规模与基于液体的合成的许多成就相比相形见绌。在材料研究部门的固态和材料化学计划以及电子和光子材料计划的财政支持下，该研究项目旨在通过一种新的合成策略来弥补这种差距，该策略依赖于在浸入液体介质中时在衬底上形成纳米结构。如果被证明是成功的，该方法将允许基于溶液的化学方法直接在基底上实践，并在此过程中建立支持传感，光化学和催化应用所需的科学。通过对暑期本科生研究实习的监督，研究活动正在与本科生教育相结合。外展活动正朝着预科妇女进入engineering professional.Technical AbstractThis研究项目旨在确定是否依赖于种子介导的胶体化学合成协议是适应于一个基于基板的平台依赖于基板固定模板。首要目标是定义形成贵金属纳米结构的有组织表面所需的化学控制和机械框架，然后通过展示所形成的等离子体和化学活性表面的功能来建立它们的技术相关性。三个推力领域推进添加剂，减性和多级模板辅助生长模式，这是依赖于异质成核和/或电镀置换过程，被用来隔离的确切作用所发挥的基板，反应动力学，pH值，模板材料和模板表面改性，在确定反应产物。目标是能够定义周期性阵列的合成协议：（i）具有高级功能的核-壳结构，其源自将具有不同物理和化学性质的材料整合到单个纳米结构体系结构中，（ii）笼状纳米结构，其提供强等离子体近场和纳米结构与其笼之间的可调间距，以及基于写入具有预定布局的图案的纳米帧。这些合成试验，结合模拟和使用基于基底的平台所特有的表征技术，提供了形成复杂纳米结构的手段，这些纳米结构的形状和组成经过设计以实现所需的响应。

Non-technical AbstractThe key enablers for transformative nanotechnologies are breakthroughs in both the synthesis of nanomaterials and an understanding of the chemistry and physics which guides their formation. Applications typically require that the nanomaterials be suspended in liquids or immobilized on planar substrates such as glass or silicon. While substrate-based nanostructure synthesis techniques have undeniably given rise to an impressive list of technologically relevant nanomaterials, the scope and scale of this success is dwarfed by the many accomplishments of liquid-based syntheses. With financial support from both the Solid State and Materials Chemistry program and the Electronic and Photonic Materials program in the Division of Materials Research, the research project aims to remedy this disparity through a new synthetic strategy reliant on forming nanostructures on substrates while immersed in a liquid medium. If proven successful, the approach will allow the solution-based chemistry which has proved so successful to be practiced directly on substrates and, in doing so, establish the science needed to support applications in sensing, photovoltaics and catalysis. Research activities are being integrated with undergraduate education through the supervision of summer undergraduate research internships. Outreach initiatives are being directed toward the matriculation of women into the Engineering profession.Technical AbstractThis research project seeks to determine whether synthetic protocols reliant on seed-mediated colloidal chemistry are adaptable to a substrate-based platform reliant on substrate-immobilized templates. The overriding goal is to define the chemical controls and mechanistic framework needed to form organized surfaces of noble metal nanostructures and then establish their technological relevance by demonstrating the functionalities of the plasmonic and chemically active surfaces formed. Three thrust areas advancing additive, subtractive and multistage template-assisted growth modes, which are reliant on heterogeneous nucleation and/or galvanic replacement processes, are being used to isolate the exact roles played by the substrate, reaction kinetics, pH, template material and template surface modifications in determining the reaction product. Being targeted are synthetic protocols able to define periodic arrays of: (i) core-shell structures with advanced functionalities derived from the integration of materials with dissimilar physical and chemical properties into a single nanostructure architecture, (ii) caged nanostructures offering intense plasmonic near-fields and tunable spacings between the nanostructure and its cage and (iii) substrate-based nanoframes written into patterns with predetermined layouts. These synthetic trials, combined with simulations and the use of characterization techniques which are unique to the substrate-based platform, are providing the means to form intricate nanostructures whose shape and composition are engineered to realize a desired response.