首页» 通知公告» 学术动态»
【学术报告】Local Environments and Molecular Engineering of Semiconductor Nanocrystals

 

报告摘要:

  (量子点)具有优异的光电性质,其发光在可见和近红外随尺寸简单可控。其在生物成像,发光器件,太阳能电池,光电探测器和量子计算上有广泛应用。量子点的微观表征与修饰,及相应的分子甚至原子工程是材料科学中最有趣的研究课题之一。在本研究中我们开发了一个磁性探针,可以灵敏探测量子点表面和核的微观环境,以及核/壳量子点的界面环境。在纳米颗粒内部进行掺杂可以有效改善其性质以实现多功能纳米材料。报告人开展了掺杂量子点的光学性能的调控及在发光器件和绿色能源的应用研究。在纳米颗粒的表面,我们采用脂质囊泡包裹的方法,有效的将疏水性量子点转移到水溶液。试验和理论研究表明脂膜的物相可以控制量子点的物理和化学性质。据此我们得到了水溶液中最光稳定的简单量子点。同时用磷脂囊泡模板和DNA碱基配我们成功的对量子点的特殊位点进行表面修饰和分子工程。由此得到的多功能纳米结构可以用于生物环境中的荧光成像和潜在药物传递。

  Semiconductor nanocrystals or named quantum dots (QDs) with unique dimension-dependent electric and optical properties are one of the most interesting materials capturing the interest of researchers over the past decades, and have broad applications in biological imaging, light-emitting devices, solar cells, photo-detectors, and quantum computing. In my study, a sensitive magnetic probe was developed to detect the microenvironments of surface and core of a QD, as well as interface of core/shell QDs. Doping inside the nanocrystals is an important method to manipulate the properties with the aim of multifunctional nanomaterials. We have used dopants to fine turn the optical properties of the nanomaterials. Surface modification such as lipid vesicle encapsulation is an efficient approach to transfer hydrophobic QDs into aqueous solutions. Our study indicates that lipid membranes can control the chemical and optical properties of QDs in a phase-dependent manner. Using gel-phase lipid vesicle templates, we are able to achieve the most photostable non-core/shell QDs in aqueous solution. More importantly, the site-specifically engineering of QDs can be achieved using phospholipid-QD hybrid vesicle templates to generate gold NP-QD assemblies programmed by Watson-Crick base-pairing for use as a multi-functional cargo for fluorescence-based imaging and potential drug delivery.