Engineered Nanoparticles for Advanced Photovoltaic, Photonic, and Imaging Applications

纳米结构材料的合成以及根据其尺寸和结构设计其特性的能力方面取得的进展将对先进的能量转换、发光和成像应用产生强烈而积极的影响。量子点（QD）由于其量子约束的性质而表现出非凡的光电和光子特性。高度可调的性质可以实现在这种纳米晶体制造与控制架构。通过利用这些结构及其接口，可以构想新一代光电器件，并在相关应用中达到新的前沿。***在本研究中，将合成具有理想性能的量子点和纳米线，并在光伏（PV）、光子和成像器件中展示新的应用。采用水包油微乳液法制备量子点溶液的胶体溶液。在制造具有高发光量子效率、稳定性和寿命的核/壳/壳和核/壳结构时，将实现不同的结构和尺寸控制。制备的量子点结构包括CdSe/ZnS、CdSe/ZnS/二氧化硅、PbS、CuInS2/ZnS。ZnO纳米线将通过水热法和自上而下的RIE蚀刻法生长，并将与量子点层结合在特定的器件设计中使用。***在UV区具有窄吸收带的QD材料将被用作光子下转换器，或用作PV器件中的发光下移器。通过将量子点嵌入聚合物宿主介质中，还可以实现可积光转换器层。除了使用光学转换器，量子点还将作为有源电子元件在量子点敏化的太阳能电池结构中实现，如平面ZnO薄膜/量子点结构，以及具有高转换效率的ZnO纳米线/量子点结构。采用合成ZnO纳米线结合QD层的新型发光器件原型将被证明可以产生白光led。此外，在探测器领域，量子点将紫外线下转换为更高（近红外）波长光子的能力也将用于制造先进的探测器设备，展示了探测波段的扩展，以包括紫外线能力。该项目将证明具有所需吸收/发射波段的集成量子点层的新型成像器件（基于ccd）的适用性。总体而言，该项目涉及具有可调谐特性的纳米结构的制造方法和表征，并通过相对简单的制造技术，为未来能源，光发射和成像应用展示先进设备

Advances being made on the synthesis of nano-structured materials and on the ability to engineer their properties emanating from their dimensions and structure will have a strong and positive impact on advanced energy conversion, light-emitting, and imaging applications. Quantum dots (QD) demonstrate extraordinary optoelectronic and photonic properties due to their very nature of quantum confinement. Highly tunable properties can be achieved in such nanocrystals fabricated with controlled architectures. By exploiting these structures and their interfaces new generations of optoelectronic devices can be conceived and new frontiers can be reached in related applications.***In the proposed research QDs and nanowires with desired properties will be synthesized and novel applications will be demonstrated in photovoltaic (PV), photonic, and imaging devices. By employing oil-in-water micro-emulsion processes colloidal solutions of QD solutions will be synthesized. Different architectures and size control will be achieved in fabricating the core/shell/shell and core/shell structures with high luminous quantum efficiency, stability, and lifetime. The QD structures to be fabricated include CdSe/ZnS, CdSe/ZnS/silica, PbS, CuInS2/ZnS. Nanowires of ZnO will be grown by hydrothermal method and also by top-down RIE etching, and will be used in specific device designs, in combination with the QD layers.***QD materials with narrow absorbtion band in the UV region will be employed as photonic down-converters, or as luminescent down-shifters in PV devices. By embedding the QDs in polymeric host media integrable optical converter layers will also be achieved. In addition to their use of optical converters, QDs will also be implemented as active electrical components in QD-sensitized solar cell structures as planar ZnO film/QD structures, and as ZnO nanowire/QD structures with high conversion efficiencies. New light emitting device prototypes employing the synthesized ZnO nanowires in combination with QD layers will be demonstrated to yield white light LEDs. Furthermore, in the firld of detectors, the ability of the QDs to down-convert UV into higher (near infrared) wavelength photons will also be utilized to fabricate advanced detector devices, demonstrating extension of the detection band to include UV capability. The project will demonstrate applicability to novel imaging devices (CCD-based) with integrated layer of QDs with the required absorption/emission bands. Overall, the project involves fabrication methodologies and characterization of nanostructures with tunable properties, and demonstrates, through relatively simple fabrication technologies, advanced devices for future energy, light emission, and imaging applications.**