EPM: Engineering Transparent Conducting Superlattices from Liquid Metal Printed 2D Oxides

EPM：利用液态金属打印的二维氧化物设计透明导电超晶格

基本信息

批准号：
2202501
负责人：
William Scheideler
金额：
$ 48.77万
依托单位：
Dartmouth College
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-01 至 2025-06-30
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2202501&HistoricalAwards=false
关键词：
EPM Engineering Transparent Conducting Superlattices

项目摘要

Nontechnical Description: Two-dimensional (2D), atomically thin materials have unique optical and electronic properties that could enable emerging technologies, from chemical sensors to low power microelectronics. However, fabricating atomically thin layers at a large-scale whilecontrolling their electrical properties remains challenging. This project seeks to harness a new class of ultrathin oxide layers formed on the surface of the molten metals gallium and indium to efficiently fabricate highly conductive and ultra-transparent nanosheets. The primary goal of this work is to thoroughly understand and precisely control the nanoscale atomic composition, crystallinity, and electron transport properties of these 2D oxide materials by stacking multiple layers and by engineering the oxidation of liquid metal alloys formed from tin, zinc, and gallium. These methods enhance the electron mobility and light transmittance, as well as tuning of the electron concentration in these materials for enabling applications to photodetectors, solar cells, and displays. Integrated with the research efforts, this plan builds on practices that have successfully engaged undergraduate students from underrepresented groups in research to train a diverse and inclusive engineering workforce. The education plan involves development of remote deployable liquid metal science demonstrations for experiential learning by undergraduates and K-12 students. This project also includes efforts to broaden graduate level STEM participation via the principal investigator’s organization and hosting of a panel discussion series in collaboration with diverse engineering student groups.Technical Description: The overarching goal of this project is to develop a new paradigm of ultra-transparent, highly flexible, and optoelectronically tunable 2D metal oxides via superlattice engineering. These high-performance transparent conducting materials leverage a fundamentally new synthetic strategy for printing 2D oxide nanosheets from the solid oxide skin of liquid metals. Initial studies of 2D oxides reveal their unique overlapping grain morphologies, quantum-confined electronic structure, and ultrahigh electron mobility. This work identifies the nanoscale material origins of these exceptional optoelectronic properties and controls the composition, crystallinity, and conductivity of multicomponent 2D oxides by engineering the physics of liquid metal surface oxidation. These studies specifically investigate how metal alloy composition impacts the logarithmic growth kinetics of surface oxidation and then connect this process physics with 2D oxides’ chemical composition through detailed material characterization. These experiments test the hypothesis that surface-driven defect modulation doping from type-II heterojunctions with insulating wide bandgap oxides (e.g. gallium oxide) can directly enhance the conductivity of 2D metal oxides. Extracting the electronic density of states in combination with optical absorption spectroscopy can also quantitatively link alloy composition with the surface oxides’ electronic structure. These studies are of broad significance because this fundamental knowledge unlocks emerging applications in flexible electronic devices including low-power emissive displays, electrochromic smart windows, and high-efficiency solar cells that demand high-performing semiconductors and transparent electrodes with tunable properties.This project is jointly funded by the Electronic and Photonic Materials program and the Established Program to Stimulate Competitive Research (EPSCoR).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.

非技术描述：二维（2D）原子薄的材料具有独特的光学和电子特性，可以使新兴技术从化学传感器到低功率微电子学。但是，在控制其电气性能的同时，在大规模上制造原子薄层仍然受到挑战。该项目旨在利用在熔融金属和ins液的表面形成的新型超薄氧化物层，以有效地制造高导电性和超透明纳米片。这项工作的主要目的是通过堆叠多层氧化氧化物材料，并通过对这些2D氧化物材料的纳米原子组成，结晶度和电子传输性能进行彻底理解和精确控制，并通过工程设计由锡，锌和胆汁形成的液态金属合金的氧化物。这些方法增强了电子迁移率和光传输，以及对这些材料中电子浓度的调整，以使光电探测器，太阳能电池和显示器应用于应用。该计划与研究工作相结合，建立在研究中成功培训多样性和包容性工程劳动力的实践的实践。该教育计划涉及开发本科生和K-12学生的远程可部署液体金属科学演示，用于专家学习。该项目还包括通过与Divers Engineering学生组合作的主要研究者组织以及主持小组讨论系列的研究生级STEM参与的努力。技术描述：该项目的总体目标是通过超透明型2D金属氧化物通过超级层次的高级发动机开发超透明，高度灵活，高度灵活，高度灵活，高度灵活，高度灵活的范围。这些高性能透明的导电材料利用了一种从根本上从液体金属固体氧化物皮肤上打印2D氧化物纳米片的新型合成策略。对2D氧化物的初步研究揭示了它们独特的重叠谷物形态，量子限制的电子结构和超高电子迁移率。这项工作确定了这些特殊光电特性的纳米级材料起源，并通过工程化液态金属表面氧化物理学来控制多组分2D氧化物的组成，结晶度和电导率。这些研究特别研究了金属合金成分如何影响表面氧化的对数生长动力学，然后通过详细的材料表征将该过程物理学与2D氧化物的化学成分联系起来。这些实验检验了以下假设：与II型异质结的表面驱动的缺陷调节掺杂，并具有绝缘的宽带胶质氧化物（例如加氧化剂）可以直接增强2D金属氧化物的电导率。将态的电子密度与光学滥用光谱结合使用也可以将合金组成与表面氧化物的电子结构进行定量联系。这些研究具有广泛的意义，因为这些基本知识解锁了在柔性的电子设备中的新兴应用，包括低功率显示器，发射式智能窗口以及高效的太阳能电池，以及要求高性能的半导体和透明电极的高效太阳能电池，并具有可调性的项目。反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响审查标准评估被认为是宝贵的支持。