Tailoring the Ionic Liquid Environment in Nanopores for Green Reaction Engineering

1604491PI：Rankin，Stephen E. 标题：为绿色反应工程定制纳米孔中的离子液体环境离子液体 (IL) 是熔点较低的盐，因此可以在室温或接近室温下用作溶剂。离子液体因其低挥发性而被认为是绿色溶剂，而且还具有独特且可调节的特性，使它们能够用于几乎没有替代品的应用，例如木质纤维素生物质向商品化学品的溶解和催化转化。 最近，离子液体的分子和纳米级结构和动力学特征已被确定，表明电荷和极性共存，这可能解释了为什么它们能够溶解两亲聚合物，如纤维素和木质素。引入表面会导致界面处的密度和电荷分层，从而产生振荡表面力和精确调节表面特性的能力。 拟议的工作重点是调整与限制在纳米孔中的金属配合物接触的离子液体的表面特性，以提供高催化性能和稳定性的局部环境。 纳米多孔载体提供了对催化剂定位的控制，创造了一个独特的环境来调节反应性并控制底物、反应物和产物的分配。该项目将把受限离子液体独特的局部溶剂和分层电子特性转化为多相催化，解决离子液体商业应用的主要限制。受限孔中的溶剂环境与相应的催化活性之间的关系将应​​用于具有挑战性的水基催化。D-葡萄糖脱水生成5-羟甲基糠醛（HMF）将被用作模型反应。提出了以下任务：（1）构建、表征和控制纳米级孔隙中离子液体和系留咪唑基离子液体的局部环境作为孔径的函数。具有定向、可调纳米孔（2-20 nm）的表面活性剂模板化二氧化硅薄膜将作为局部环境表征和离子液体后续催化的平台。 (2) 设计离子液体/金属配体及其相应的硅烷，将离子液体中的均相催化转化为纳米级孔中有效、稳定的多相催化剂。将研究使用无毒铝基催化剂将葡萄糖脱水为 HMF，目标是提高其催化性能，使其成为传统有毒催化剂的可行替代品。 (3) 演示葡萄糖从水相催化成 HMF 的过程，并开发有限的 IL 孔隙环境，最大限度地减少因吸水而导致的催化剂失活和浸出。拟议的研究项目有潜力产生创新的绿色/可持续化学和工程技术，广泛应用于催化、能源储存、光伏、气体分离和二氧化碳捕获等领域。 其中包括开发基于视频的传播计划（视频-CATS）的多方面计划，该计划将培训学生如何向不同的受众传播科学，以造福社会。

1604491PI: Rankin, Stephen E. Title: Tailoring the Ionic Liquid Environment in Nanopores for Green Reaction EngineeringIonic liquids (ILs) are salts with a low melting temperature such that they can be used as solvents at or near room temperature. ILs are considered green solvents because of their low volatility, but also have unique and tunable properties that allow them to be used in applications where few alternatives are available, such as the solubilization and catalytic conversion of lignocellulosic biomass to commodity chemicals. Recently, molecular and nanometer-scale structural and dynamic features of ILs have been identified that indicate coexisting domains of both charge and polarity, which may explain why they are able to dissolve amphiphilic polymers, such as cellulose and lignin. Introducing a surface leads to density and charge layering at the interface giving rise to oscillatory surface forces and the ability to precisely tune surface properties. The proposed work focuses on tuning these surface properties for ILs in contact with metal complexes confined in nanopores to provide a local environment for high catalytic performance and stability. Nanoporous supports provide control in localizing a catalyst, creating a distinct environment for tuning reactivity and controlling the partitioning of substrates, reactants and products. This project will translate the unique local solvent and layered electronic properties of confined ILs to heterogeneous catalysis, addressing the major limitations of the commercial applications of ILs. The relationship between the solvent environment in the confined pore and the corresponding catalytic activity will be applied to challenging aqueous-based catalysis.The dehydration of D-glucose to 5-hydroxymethylfurfural (HMF) will be used as a model reaction. The following tasks are proposed: (1) Construction, characterization and control the local environment of ionic liquids and tethered imidazolium-based ionic liquids in nanoscale pores as a function of pore size. Surfactant templated silica thin films with oriented, tunable nanopores (2-20 nm) will serve as the platform for characterization of the local environment and subsequent catalysis in ionic liquids. (2) Design of IL/metal ligands and their corresponding silanes to translate homogeneous catalysis in ILs to effective, stable heterogeneous catalysts in nanoscale pores. The dehydration of glucose to HMF using non-toxic aluminum-based catalysts will be investigated, with a goal of improving its catalytic performance to make it a viable alternative to traditional toxic catalysts. (3) Demonstration of the catalysis of glucose to HMF from the aqueous phase and development of a confined IL pore environment that minimizes catalyst deactivation and leaching due to water uptake.The proposed research project has the potential to generate innovative green/sustainable chemistry and engineering technologies for a broad range of applications in catalysis, energy storage, photovoltaics, gas separations, and carbon dioxide capture. Multi-faceted plans to develop a video-based communication program (video-CATS) are included, which will train students on how to communicate science for the benefit of society to a diverse audience.