Metal-Sensitive Functionalization and Self-Assembly of Bimetallic Nanocrystals

双金属纳米晶的金属敏感功能化和自组装

基本信息

批准号：
2002653
负责人：
Younan Xia
金额：
$ 45万
依托单位：
Georgia Tech Research Corporation
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2002653&HistoricalAwards=false
关键词：
Metal Sensitive Functionalization Self Assembly

项目摘要

The Macromolecular, Supramolecular, and Nanochemistry Program in the Chemistry Division supports Professor Dong Qin and her group at the Georgia Institute of Technology to develop tiny crystals called bimetallic nanocrystals. Their bimetallic nanocrystals contain two metals whose chemical function and spatial position within the nanocrystals are precisely controlled. Metal nanocrystals play a vital role in enabling catalysis for energy conversion, environmental protection, and organic synthesis. Despite some success, it remains a daunting challenge to monitor the catalytic reactions in real time by spatially confining the reactants to the catalytic sites while detecting the final and intermediate products in situ. The research team addresses this challenge by developing bimetallic nanocrystals in which one of the metals can serve as a catalyst while the other can report the ‘chemical fingerprint’ (signals associated with the reaction). The concepts, materials, and methods developed during this research may find use in a broad range of applications related to solid-state chemistry, catalysis, sensing, and photonics. This team recruits women and minority students as well as those from community colleges and minority institutions for summer research. This effort is carried out in collaboration with the National Nanotechnology Coordinated Infrastructure called the Southeastern Nanotechnology Infrastructure Corridor. In this research supported by the Macromolecular, Supramolecular and Nanochemistry (MSN) Program, Professor Qin’s team develops new design principles and methods to fabricate a novel class of bifunctional nanoreactors from Ag@M (M: Pt, Pd, and Rh) core-frame nanocubes via metal-selective surface functionalization and self-assembly. Specifically, molecules bearing isocyanide groups at the two ends are used to selectively bind to the M atoms on the edges of the core-frame nanocubes, serving as “clips” to bring two nanocubes face to face for the generation of a dimer. The gap region between the two nanocubes naturally presents a well-controlled nanoreactor, in which the side faces can be orthogonally functionalized with the reactants while the M atoms not coordinated by isocyanide will serve as the catalyst. Due to a strong plasmonic coupling between the two Ag nanocubes separated by a gap of only a few nanometers, the nanoreactor offers a unique capability to monitor various types of important catalytic reactions by in situ SERS. The model reactions include the hydrogenation of nitroaromatics for the production of thermodynamically unfavorable products such as hydroxylamine and azo compounds, as well as the bond-selective hydrogenation of cinnamaldehyde, a catalytic reaction pivotal to the production of fragrance, agrochemical, and pharmaceutical compounds. This research not only enables real-time characterization of heterogeneous catalytic reactions but also sheds light on the rational design of new or improved catalyst materials.This 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.

化学部的大分子，超分子和纳米化学计划支持佐治亚理工学院的Dong Qin及其小组，以开发称为双金属纳米晶体的微小晶体。它们的双金属纳米晶体包含两种金属，其化学功能和空间位置在纳米晶体中得到精确控制。金属纳米晶体在使能量转化，环境保护和有机合成的催化中起着至关重要的作用。尽管取得了一些成功，但通过将反应物限制在催化位点的同时，在检测最终和中间产品的原位，实时监测催化反应仍然是一个艰巨的挑战。研究小组通过开发双金属纳米晶体来应对这一挑战，其中一种金属可以作为催化剂，而另一个可以报告“化学指纹”（与反应相关的信号）。在这项研究期间开发的概念，材料和方法可能会在与固态化学，催化，灵敏度和光子学有关的广泛应用中使用。该团队报告了妇女和少数民族学生以及社区大学和少数民族机构的夏季研究。这项工作是与称为东南纳米技术基础设施走廊的国家纳米技术协调基础设施合作进行的。在这项研究的支持下，由大分子，超分子和纳米化学（MSN）计划支持，QIN教授的团队发展新设计原理和方法，以通过AG@m（M：M：PT，PT，PD，PD和RH）核心纳米型纳米型纳米构造的纳米型纳米型纳米型纳米构造纳米构造的纳米构造型纳米型纳米构造型纳米型纳米构造型纳米构造的表面效果和自我效果。具体而言，两端的轴承异氰化物基团的分子用于选择性地与核心框纳米纸的边缘的M原子结合，用作“夹子”，以使两个纳米容器面对面对二聚体的产生。两种纳米管之间的间隙区域自然显示出良好的控制纳米反应器，其中侧面可以与反应物正交功能化，而不是由异氰酸酯协调的M原子将用作催化剂。由于两种Ag纳米纸之间的等离激元耦合仅由几个纳米隔开，因此纳米反应器具有独特的能力，可通过原位SERS监测各种类型的重要催化反应。该模型反应包括硝化产物的氢化，用于生产热力学不利的产物，例如羟胺和氮杂化合物，以及肉桂醛的键选择性氢化，这是一种催化反应，可促催化反应，以产生香料，农业化学和药物化合物的产生。这项研究不仅可以实时表征异质性催化反应，而且还阐明了新的或改进的催化剂材料的合理设计。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛影响标准的智力优点通过评估来获得的支持。