Disentangling Relationships among Dopant Structure, Dopant and Polymer Energetics, Thin-Film Morphology, and the Electrical Properties of Doped Conducting Polymer Films

阐明掺杂剂结构、掺杂剂和聚合物能量学、薄膜形态以及掺杂导电聚合物薄膜的电性能之间的关系

• 批准号: 1905734
• 负责人: Kenneth Graham
• 金额: $ 45.22万
• 依托单位: University of Kentucky Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905734&HistoricalAwards=false
• 关键词: Disentangling; Relationships; among; Dopant; Structure

Organic semiconductors promise to enable new generations of low-cost, mechanically flexible, and wearable electronic devices. Their potential uses are only beginning to be realized on the commercial scale with the recent widespread adoption of organic light emitting diodes (OLED) in cell phone and tablet displays and televisions. Further, these materials are being explored for use in solar cells, electronic circuitry, sensors, and thermoelectric devices that are printed directly from solution. In many cases, organic semiconductors are chemically doped with molecules that introduce charge carriers to make the materials more electrically conductive, as is desirable for many applications. For example, chemical doping is used in OLED to increase brightness and power efficiency. Improving the performance and stability of doped organic semiconductors is critical to the further development of electronic devices in which they may be used, yet it is extremely difficult to predict how a chemical dopant will affect the electronic properties of an organic semiconductor. This research uses a tightly integrated experimental and theoretical approach to disentangle variables that influence the electronic properties of doped organic semiconductors, with the goal of enhancing the material performance and stability across multiple potential applications. In addition to accelerating the development of applications based on organic semiconductors, the proposal aims to promote interest, engagement, and participation in STEM disciplines through exposing high school students throughout the state of Kentucky to the exciting technologies enabled by organic semiconductors. In part, this goal involves a workshop where high school students make electrochromic devices, where a material changes color through electrochemical doping, and thermoelectric devices, where a material harvests heat and turns it into electricity, and learn about the power of computational chemistry.The electronic and thermoelectric properties of doped organic semiconductors remain extremely difficult to predict due to the interplay of multiple variables and a lack of understanding of how each variable impacts the material properties. This research seeks to advance the state-of-the-art of doped organic semiconductors by refining models of their electronic structure and transport characteristics based on a highly integrated experimental and theoretical approach. The three primary research objectives are to determine the influence of the dopant size on the material electronic structure, establish critical connections between doped conjugated polymer energetics and morphology with dopant size and diffusion, and ascertain the influence of doped conjugated polymer electronic structure and morphology on the electrical conductivity and Seebeck coefficient of materials of interest for thermoelectric applications. The research approach involves application of ultraviolet and inverse photoelectron spectroscopy on model systems coupled with quantum-chemical calculations and molecular dynamics simulations to determine the influence of dopant size and polymer morphology on electronic structure. Furthermore, electrical conductivity and Seebeck measurements on electrochemical transistors combined with kinetic Monte Carlo simulations will uncover how energetics and morphology influence charge-carrier transport and thermoelectric performance. The overall objective of the research is to establish clear relationships between dopant molecular structure, organic semiconductor electronic structure, and doped organic semiconductor morphology, electrical conductivity, and the Seebeck coefficient. These findings are key to enable better predictive design of doped organic semiconductors with controlled electronic properties.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.

有机半导体有望使新一代低成本、机械灵活和可穿戴的电子设备成为可能。随着最近有机发光二极管(OLED)在手机、平板显示器和电视中的广泛采用，它们的潜在用途才刚刚开始在商业规模上实现。此外，这些材料正在被探索用于太阳能电池、电子电路、传感器和直接从溶液打印的热电设备。在许多情况下，有机半导体被化学掺杂引入电荷载流子的分子，以使材料更具导电性，这在许多应用中是可取的。例如，在OLED中使用化学掺杂来增加亮度和功率效率。提高掺杂有机半导体的性能和稳定性是进一步发展可用于其中的电子器件的关键，然而，预测化学掺杂剂将如何影响有机半导体的电子性质是极其困难的。这项研究使用紧密结合的实验和理论方法来解开影响掺杂有机半导体电子性质的变量，目的是在多种潜在的应用中提高材料的性能和稳定性。除了加快基于有机半导体的应用程序的开发，该提案还旨在通过让肯塔基州的高中生接触到有机半导体带来的令人兴奋的技术来促进对STEM学科的兴趣、参与度和参与度。在一定程度上，这个目标涉及一个研讨会，在那里，高中生制作电致变色设备和热电设备，在那里，材料通过电化学掺杂改变颜色，在热电设备中，材料收集热量并将其转化为电能，并学习计算化学的力量。由于多个变量的相互作用，以及对每个变量如何影响材料性能的缺乏了解，掺杂有机半导体的电子和热电性能仍然非常难以预测。这项研究试图通过基于高度集成的实验和理论方法来完善掺杂有机半导体的电子结构和输运特性的模型，来推进掺杂有机半导体的最新发展。三个主要的研究目标是确定掺杂尺寸对材料电子结构的影响，建立掺杂共轭聚合物的能级和形态与掺杂尺寸和扩散之间的关键联系，以及确定掺杂共轭聚合物的电子结构和形态对热电应用中感兴趣的材料的电导率和塞贝克系数的影响。研究方法包括在模型系统中应用紫外光电子能谱和逆光电子能谱，结合量子化学计算和分子动力学模拟来确定掺杂剂尺寸和聚合物形态对电子结构的影响。此外，电化学晶体管的电导率和塞贝克测量与动力学蒙特卡罗模拟相结合，将揭示能量和形貌如何影响载流子输运和热电性能。研究的总体目标是建立掺杂剂分子结构、有机半导体电子结构与掺杂有机半导体形态、电导率和塞贝克系数之间的明确关系。这些发现是使具有受控电子性能的掺杂有机半导体能够更好地进行预测性设计的关键。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Photoactivated p-Doping of Organic Interlayer Enables Efficient Perovskite/Silicon Tandem Solar Cells

有机中间层的光激活 p 掺杂可实现高效的钙钛矿/硅串联太阳能电池

• DOI: 10.1021/acsenergylett.2c00780
• 发表时间: 2022
• 期刊: ACS Energy Letters
• 影响因子: 22
• 作者: Zheng, Xiaopeng;Liu, Jiang;Liu, Tuo;Aydin, Erkan;Chen, Min;Yan, Wenbo;De Bastiani, Michele;Allen, Thomas G.;Yuan, Shuai;Kirmani, Ahmad R.
• 通讯作者: Kirmani, Ahmad R.

n-type charge transport in heavily p-doped polymers

• DOI: 10.1038/s41563-020-00859-3
• 发表时间: 2021-01-04
• 期刊: NATURE MATERIALS
• 影响因子: 41.2
• 作者: Liang, Zhiming;Choi, Hyun Ho;Graham, Kenneth R.
• 通讯作者: Graham, Kenneth R.

Probing transport energies and defect states in organic semiconductors using energy resolved electrochemical impedance spectroscopy

使用能量分辨电化学阻抗谱探测有机半导体中的输运能量和缺陷态

• DOI: 10.1002/admi.202202256
• 发表时间: 2023
• 期刊: Advanced Materials Interfaces
• 影响因子: 5.4
• 作者: Shahi, Maryam;Atapattu, Harindi R.;Baustert, Kyle N.;Anthony, John E.;Brill, Joseph W.;Johnson, Stephen;Graham, Kenneth R.
• 通讯作者: Graham, Kenneth R.