Chemical Transformation Networks using Ultra-small Particles

1纳米尺度的纳米粒子由数十到数千个原子组成，它们的材料特性敏感地依赖于组成原子的数量，而几纳米尺度的纳米粒子基本上被认为是整体的。本项目研究这些超小纳米颗粒的二维或三维网络，诱导电子、原子、分子和离子的探测、传导、分解、转化和存储。本研究分为1个部分。2.高功能化超小颗粒的合成；3.将它们连接成网络；评估他们的设备特性。特别注意的是生产实际有用的II-VI半导体化合物的最小颗粒，成功地找到了原子精确和完全单尺寸的1纳米（CdSe）_n颗粒。组成原子的数量少于一百个，并且足够小，粒子的行为就像分子一样，可以在原子尺度和精度下连接或组装。它们展示了由大块晶体结构无法实现的特殊原子排列所产生的特性所实现的功能器件，为纳米科学和技术开辟了一条新途径。在n= 13,34,48,60....的条件下合成了（CdSe）_n的超小颗粒这样的小粒子表现出对组成原子数目n极其敏感的稳定性，因此只能在这些n处选择性地生长。这些粒子的网络不仅通过简单的阵列形成，而且通过它们与有机聚合物形成二维和三维排列而产生。这些1nm颗粒通过三辛基膦（TOP）等表面改性进一步功能化，产生与商用有机染料罗丹明相当的极高发光效率。这些功能是通过我们的原子精确合成和表征实现的，因为它们的分子性质，被证明是纳米科学和技术的理想方法。少

Nanoparticles in 1 nm dimension consisting of tens to thousands of atoms exhibit materials properties sensitively dependent on the number of constituent atoms, in contrast to those over a few nm which are regarded essentially as the bulk. This project investigates two or three dimensional networks of these ultra-small nanoparticles inducing detection, conduction, decomposition, transformation, storage of electrons, atoms, molecules and ions.The research is divided into 1.synthesis of ultra-small particles of high functionalities, 2.linking them into networks, and 3.evaluating their device characteristics. The special attention was focused on producing the smallest particles of practically useful II-VI semiconducting compounds, succeeding in finding atomically precise and perfectly monosized 1 nm particles of (CdSe)_n. The number of constituent atoms is less than a hundred and is small enough that the particle behaves like a molecule to be linked or assembled under atomic scale and prec … More ision. They exhibit functional devices realized by and based on the properties arising from special atomic arrangements not achieved by bulk crystalline structures, leading to a new approach in nanometer science and technology.Ultra-small particles of (CdSe)_n were synthesized with n= 13,34,48,60.... Such small particles exhibit their stabilities extremely sensitive to the number of constituent atoms, n, so as to be selectively grown only at these n's.Networks with these particles were produced not only by simple array formation but also by their liking with organic polymers to form two and three dimensional arrangements.These 1nm particles are further functionalized by surface modification with such as trioctylphosphine (TOP) to yield extremely high luminescence efficiency comparable to rhodamines of commercial organic dyes.These functionalities are realized by our atomically precise synthesis and characterization made possible because of their molecular nature, proven as a desirable approach in the nanoscience and technology. Less