EAGER: Nanostructure-Enabled Solution Catalysis with Concentration Gradients

有了这个奖项，美国国家科学基金会化学部的化学催化计划正在资助加州大学洛杉矶分校的Chong Liu博士，以探索溶液催化中的新化学和反应性，其中反应物和催化剂的浓度在太空中得到控制。从基础研究到工业生产的化学转化通常在溶液中进行。通常，各种化学物质均匀地分散在整个溶液中。虽然这通常简化了化学过程，但它也可能是一种限制。例如，一些反应物可能彼此不相容，它们的反应导致不期望的副反应和浪费。在这些情况下，保持这些物质分离是有利的。 刘博士正在通过使用纳米级导线阵列的电化学来完成这一挑战。拟议工作的成功实施可能会提供一个新的化学合成范式，涉及纳米科学，电化学和催化的多方面方法。刘博士的研究团队，包括来自代表性不足群体的妇女和学生，将在这个项目中从事高度跨学科的研究。 Liu博士和他的团队假设，纳米线阵列的电化学在显微镜下产生可控的局部O2梯度，这使得O2敏感的有机金属催化剂能够进行氧化反应，例如直接将甲烷（CH 4）转化为甲醇（CH 3OH）。Liu博士的研究小组将设计和表征线阵列电极产生的浓度梯度，在环境条件下使用O2氧化剂建立O2失活催化剂的选择性CH 4-to-CH 3OH转化，并探索受益于浓度梯度的溶液催化的其他场景。本研究建立了具有浓度非均匀性的均相催化的设计原理，通过解决两个重要问题：（1）如何在微观尺度上利用电势来控制和产生预先设计的浓度分布？(2)通过建立微观浓度梯度，溶液催化可以得到哪些改进？纳米科学和均相催化的整合提供了一种独特的和潜在的强大的方法来控制反应在分子和微观长度scalesThis奖项反映了NSF的法定使命，并已被认为是值得支持的，通过评估使用基金会的知识价值和更广泛的影响审查标准。

With this award, the Chemical Catalysis Program of the NSF Division of Chemistry is funding Dr. Chong Liu of the University of California, Los Angeles to explore new chemistry and reactivity in solution catalysis where the concentrations of reactants and catalysts are controlled in space. Chemical transformations ranging from fundamental investigations to industrial manufacturing are often conducted in solution. It is usually true that the various chemical species are uniformly dispersed throughout the solution. While this often simplifies chemical processes it can also be a limitation. For example, some reactants may not be compatible with each other, with their reactions leading to undesirable side reactions and waste. In these cases it is advantageous to keep these species separated. Dr. Liu is accomplishing this challenge with electrochemistry using arrays of nanometer scale wires. Successful implementation of the proposed work would potentially offer a new paradigm in chemical synthesis with a multifaceted approach involving nanoscience, electrochemistry, and catalysis. Dr. Liu's research team, including women and students from underrepresented groups, will be engaged in highly interdisciplinary research in this project. Dr. Liu and his team hypothesize that the electrochemistry of nanowire arrays yields controllable local O2 gradient microscopically, which enables O2-sensitive organometallic catalysts to perform oxidative reactions such as direct methane (CH4) to methanol (CH3OH) conversion. Dr. Liu’s research group will design and characterize concentration gradients generated by wire array electrodes, establish a selective CH4-to-CH3OH conversion of O2-deactivating catalysts with O2 oxidant at ambient condition, and explore additional scenarios of solution catalysis that benefits from concentration gradients. This project establishes the design principle of homogenous catalysis with concentration heterogeneity, by addressing two important questions: (1) How can one use electric potential to control and generate a pre-designed concentration profile at microscopic scale? (2) What improvements can be attained for solution catalysis via the establishment of microscopic concentration gradients? The integration of nanoscience and homogenous catalysis provides a unique and potentially powerful approach to control reactions at both molecular and microscopic length scalesThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.