Active Hybrid Nanocrystal-Carbon Nanotube Structures for Optoelectronic Devices

用于光电器件的有源纳米晶-碳纳米管结构项目概述本提案提出了一项用于光电子学应用的有源纳米晶-碳纳米管(CNT)结构领域的综合研究和教育计划。提出的研究计划旨在促进对新型杂化纳米结构的基本认识和光电子器件的应用。该项目的具体目标是：(1)以受控方式制备各种纳米晶-碳纳米管杂化结构；(2)通过表征杂化纳米结构的性质，特别是纳米晶与碳纳米管在各种气体和光调制下的电子和物理相互作用，探索纳米晶与碳纳米管之间的电子传导机制；(3)探索将杂化半导体纳米晶或量子点(QD)-碳纳米管纳米结构用于光伏电池。纳米晶-碳纳米管杂化结构代表了一类新的纳米材料，它不仅可能显示纳米晶和碳纳米管的独特性质，而且由于纳米晶和碳纳米管之间的相互作用，还可能显示出额外的新性质。可控杂化纳米结构及其基本特性的出现将为纳米科学和纳米技术开辟新的机会，并将加速发现和发明。这种混合纳米结构可以对刺激(例如，光和气体)做出反应，因此是“活跃的”。纳米晶体和碳纳米管的协同响应可用于各种创新设备应用，包括光伏电池、气体传感器和生物传感器。将气溶胶或胶体纳米晶沉积到碳纳米管上的一般静电导向组装技术在创建所需的杂化纳米结构方面是方便和灵活的。通过多种技术对杂化纳米结构性质的详细表征将提供对电子/物理相互作用以及纳米晶体和碳纳米管之间的电子传导机制的物理见解。新的光伏电池结构将利用碳纳米管的高电子迁移率，纳米晶体和碳纳米管之间的高效电子转移，碳纳米管-量子点(QD)界面的有效电荷分离，以及量子点的许多优点，例如通过合理选择QD材料和尺寸来微调光吸收的潜力，以及每个光子产生多个电子-空穴对的可能性。因此，该项目还将带来具有成本效益的太阳能电池，用于收集丰富的、可再生的、清洁的太阳能，以帮助缓解我们的全球能源问题。广泛的影响：该项目的更广泛影响是深远的，因为该项目的成果将使具有最佳性能的混合纳米晶体-碳纳米管结构的广泛创新应用可以根据特定条件量身定做。新的光伏电池将有助于减少我们对化石燃料的依赖，以及温室气体排放对环境的不利影响。拟议的研究被广泛纳入教育目标，以促进变革性和跨学科的工程教育，以吸引更多未被充分代表的学生进入科学、技术、工程和数学(STEM)领域，并广泛传播纳米技术成果。拟议的工程教育计划将帮助我们的学生在快速变化的环境中变得更加适应和创新。现有的NSF REU计划和UWM的本科生研究荣誉计划将被利用，让本科生研究人员参与进来。该项目将通过关于混合纳米结构和将小型纳米技术项目纳入现有课程的课程模块，接触到更广泛的学生群体。特别努力通过科学星期六激励未被充分代表的大学预科学生？通过指导科学项目，将吸引更多未被充分代表的学生进入STEM领域。通过在NSF赞助的高影响力的国家学习与教学中心网站上张贴课程模块、与密尔沃基探索世界博物馆联合举办纳米技术展览、与威斯康星职业学院合作举办地区性科学博览会，将有效地向广泛的受众传播新技术。

Active Hybrid Nanocrystal-Carbon Nanotube Structures for Optoelectronic DevicesProject SummaryThis proposal presents an integrated research and education plan in the area of active hybrid nanocrystal-carbon nanotube (CNT) structures for optoelectronic applications. The proposed research program aims to advance the fundamental understanding and the optoelectronic device application of the novel hybrid nanostructures. Specific goals of the project are: (1) to produce various hybrid nanocrystal- CNT structures in a controlled fashion; (2) to probe the electronic transduction mechanism between the nanocrystal and the CNT through the characterization of properties of hybrid nanostructures, particularly electronic and physical interactions between the nanocrystal and the CNT under various gas and optical modulations; (3) to explore the use of hybrid semiconductor nanocrystal or quantum dot (QD)-CNT nanostructures for photovoltaic cells.Intellectual Merit: The proposed research is potentially transformative and is based on results from the PI?s earlier exploratory studies. Hybrid nanocrystal-CNT structures represent a new class of nanomaterials that could potentially display not only the unique properties of nanocrystals and those of CNTs, but also additional novel properties due to the interaction between the nanocrystal and the CNT. The availability of controlled hybrid nanostructures and their fundamental properties will open up new opportunities for nanoscience and nanotechnology and will accelerate discoveries and inventions. The hybrid nanostructures can respond to stimuli (e.g., light and gas) and thus are " active." The synergistic response from the nanocrystal and the CNT can be harnessed for various innovative device applications, including photovoltaic cells, gas sensors, and biosensors. The generic electrostatic force directed assembly technique to deposit either aerosol or colloidal nanocrystals onto CNTs is facile and flexible in creating desired hybrid nanostructures. Detailed characterization of the hybrid nanostructure properties through a number of techniques will provide physical insights into electronic/physical interactions and the electronic transduction mechanism between nanocrystals and CNTs. The new architecture for photovoltaic cells will take advantage of the high electron mobility in CNTs, efficient electronic transfer between nanocrystals and CNTs, effective charge separation at the CNT-quantum dot (QD) interface, and many virtues of QDs, such as the potential for fine-tuning optical absorption through judiciously selecting QD materials and sizes, and the possibility of multiple electron-hole pair generation per photon. Therefore, this project will also lead to cost-effective solar cells for harvesting abundant, renewable, clean solar energy to help relieve our global energy problem.Broader Impacts: The broader impacts of this project are far-reaching, as the project results will enable a wide range of innovative applications of hybrid nanocrystal-CNT structures with optimum properties that can be tailored for specific conditions. The new photovoltaic cells will help reduce our dependence on fossil fuels and their associated adverse environmental effects due to greenhouse gas emissions. The proposed research is extensively integrated into educational goals to promote transformative and interdisciplinary engineering education to attract more underrepresented students into science, technology, engineering, and mathematics (STEM) fields, and to broadly disseminate nanotechnology findings. The proposed engineering education plan will help our students to become more adaptive and innovative in rapidly changing environments. The existing NSF REU program and the undergraduate honors in research program at UWM will be leveraged to involve undergraduate researchers. The project will reach the broader student population through a course module on hybrid nanostructures and integration of small nanotechnology projects into existing curricula. Special efforts to inspire underrepresented pre-college students through ?Science Saturdays? and by mentoring science projects will attract more underrepresented students to STEM fields. Additional outreach through a course module to be posted on a high-impact NSF-sponsored National Center for Learning and Teaching Web site, a nanotechnology exhibit in conjunction with Milwaukee Discovery World Museum, and regional science fairs in collaboration with Wisconsin Career Academy, will effectively disseminatenanotechnology to a wide range of audiences.