Surface and Interface Effects on Photovoltaic and Light-Emitting Characteristics of Colloidal Nanocrystal Heterostructures

非技术描述：半导体使许多技术成为可能，包括计算机、太阳能电池和LED照明。使半导体材料足够小，从而改变其尺寸和形状，从而大大改变其光学和电学特性的新能力，为提高器件效率铺平了新的道路，更重要的是，赋予它们新的功能。该项目研究和改进了这种可以用相对简单的方法合成和加工的半导体，使用化学溶液。这些材料可以在设备中实现新的或多种功能，例如，允许显示屏中的像素不仅发出光，而且还能感应光。这种能力可能反过来简化智能手机和平板电脑等电子产品的设计和制造，为它们注入多种新功能，同时减少它们的尺寸、重量和能耗。面对多方面的挑战，为学生提供了丰富的教育和培训机会，帮助他们更好地准备成为跨学科科学和工程领域的领导者。研究计划致力以该项目的研究成果为基础，提升教学质素，并向公众推广新兴科技的益处。技术描述：胶体量子点，特别是它们的异质结构，可以通过简单的解决方法进行处理，通过简化制造工艺，提高器件性能和新的功能能力，产生了新的机会。将这些材料纳入电子/光电器件的核心是了解它们的表面和界面如何影响这些材料内外载流子的放置。反过来，利用不同的表面/界面来控制这些基本过程，从而改善器件特性，对于为下一代包含新兴纳米级材料的器件铺平道路至关重要。本项目研究了影响胶体量子点组成的器件的光电和电致发光特性的关键表面和界面因素，特别是它们的各向异性异质结构。不同的组成和形状提供了对表面/界面效应、底层能带结构和形状/各向异性之间相互作用的更深入的理解。所获得的知识应广泛适用于设计具有适当表面和界面的新材料，以从根本上改善设备的性能和能力。该项目的研究工作与教育和外展工作是协同的。研究成果激发了教学和指导活动，影响了教育，同时也提高了公众对基础科学的兴趣。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical Description: Semiconductors have enabled numerous technologies including computers, solar cells and LED lighting. The emerging ability to make semiconductor materials sufficiently small such that varying their size and shape drastically alters their optical and electrical properties is paving new paths to improving device efficiencies and, more importantly, imparting them with new capabilities. This project examines and improves on such semiconductors that can be synthesized and processed by relatively simple means, using chemical solutions. These materials can enable new or multiple functions in devices, for example, allowing a pixel in a display screen to not only emit but also sense light. Such a capability may in turn simplify the design and manufacturing of electronics such as smart phones and tablets, to imbue them with multiple new functionalities while reducing their size, weight, and energy consumption. Multi-faceted challenges to be tackled here provide ample educational and training opportunities for the students involved, helping them be better prepared to become leaders in interdisciplinary science and engineering fields. The PI is committed to building on the research results of this project to enhance teaching and promote benefits of emerging science and technologies to the general public.Technical Description: Colloidal quantum dots and, in particular, their heterostructures that can be processed through simple solution means are generating new opportunities through simplified fabrication processes, improved device performance and new functional capabilities. Central to incorporating these materials into electronic/optoelectronic devices is the understanding of how their surfaces and interfaces affect placement of charge carriers in and out of these materials. In turn, exploiting different surfaces/interfaces to control these fundamental processes and therefore improve device characteristics is essential in paving the path to the next generation of devices incorporating emerging nanoscale materials. This project examines critical surface and interfacial factors that impact photovoltaic and electroluminescence characteristics of devices consisting of colloidal quantum dots and in particular, their anisotropic heterostructures. Varying composition and shape provides a deeper understanding of the interplay between surface/interface effects, the underlying band structure, and shape/anisotropy. The knowledge gained should be broadly applicable to designing new materials with appropriate surfaces and interfaces for radically improved device performance and capabilities. The research endeavors of this project are synergistic with education and outreach efforts. Research findings inspire teaching and mentoring activities, impacting education while also promoting interest in fundamental science among the general public.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.