Exploring Spin-Orbital Coupling Effects: 3D to 2D Perovskite Solar Cells

探索自旋轨道耦合效应：3D 至 2D 钙钛矿太阳能电池

• 批准号: 1911659
• 负责人: Bin Hu
• 金额: $ 39.01万
• 依托单位: University of Tennessee Knoxville
• 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: 2019-07-15 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1911659&HistoricalAwards=false
• 关键词: Exploring; Spin; Orbital; Coupling; Effects

Non-technical:Organic-inorganic halide perovskites have shown promise for solar cells with performance approaching that of commercially available devices. These devices could transform the solar energy landscape, given the promise for low-cost manufacturing of flexible devices. Further advances require a deeper understanding of structure-property relationships. This project plans to study the fundamental properties of perovskites. The focus will be on spin-orbit coupling, which connects optical, electrical, and magnetic properties. These studies will combine materials processing, device engineering, and dynamic measurements. The goal is to achieve a deeper understanding of these materials and advance the performance of perovskite solar cells. The project will impact graduate and undergraduate students through outreach and new curriculum. The PI will also recruit and involve students from underrepresented groups in science and engineering.Technical:The proposed project will experimentally investigate spin-orbital coupling (SOC) effects in organic-inorganic hybrid halide perovskite solar cells ranging from 3D to 2D designs. The recent success of perovskite solar cells stems from the high absorption coefficient, efficient dissociation of excited states, and superior carrier transport that simultaneously occur within spin-orbital coupling framework. However, in-depth fundamental studies are timely needed to further advance the research and development of perovskite solar cells by revealing deeper structure-property relationships in both excited state and carrier dynamics. The objective of this project is to understand the SOC effects under doping, structural ordering, and external stimuli. The goal of this research is to reveal the underlying mechanisms to tune SOC effects, Rashba effects, and spin mixing towards providing innovative mechanisms to further advance photovoltaic functionalities in organic-inorganic hybrid halide perovskites. This project plans to achieve three critical goals: (i) reveal innovative mechanisms of doping-tunable SOC, (ii) explore SOC effects on direct/indirect band transitions through Rashba effect, and (iii) elucidate SOC effects on spin mixing between dark and bright states, in hybrid halide perovskites ranging from 3D to 2D designs. The proposed research will be performed by integrating three major interdisciplinary efforts from materials processing, device engineering, and experimental measurements, to explore SOC effects. The materials processing effort will prepare both 3D and 2D perovskites with different polarizations and structural symmetries/asymmetries to provide a fundamental platform to explore SOC effects. The device engineering effort will prepare state-of-the-art perovskite solar cells from 3D to 2D structures. The experimental measurements will include magnetic field effects, light polarization-modulated photocurrent/photoluminescence, time-resolved photoluminescence spectroscopy, and pump-probe transient absorption to reveal underlying mechanisms towards controlling SOC effects in hybrid halide perovskites ranging from 3D to 2D designs upon introducing doping, structural ordering, and external stimuli. Overall, the project will elucidate the key factors of controlling SOC effects, Rashba effects, and spin mixing towards fundamentally advancing perovskite photovoltaic devices.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.

非技术性：有机-无机卤化物钙钛矿已显示出太阳能电池的前景，其性能接近商用设备。鉴于柔性设备低成本制造的前景，这些设备可以改变太阳能格局。进一步的进步需要对结构-性能关系有更深入的理解。该项目计划研究钙钛矿的基本特性。重点是自旋轨道耦合，它连接光学、电学和磁学特性。这些研究将结合材料加工、设备工程和动态测量。目标是更深入地了解这些材料并提高钙钛矿太阳能电池的性能。该项目将通过推广和新课程影响研究生和本科生。 PI 还将招募来自科学和工程领域代表性不足的群体的学生。技术：拟议的项目将通过实验研究从 3D 到 2D 设计的有机-无机混合卤化物钙钛矿太阳能电池中的自旋轨道耦合 (SOC) 效应。钙钛矿太阳能电池最近的成功源于高吸收系数、有效的激发态解离以及在自旋轨道耦合框架内同时发生的优异载流子传输。然而，需要及时进行深入的基础研究，通过揭示激发态和载流子动力学中更深层次的结构-性能关系来进一步推进钙钛矿太阳能电池的研究和开发。该项目的目标是了解掺杂、结构有序和外部刺激下的 SOC 效应。这项研究的目标是揭示调节 SOC 效应、Rashba 效应和自旋混合的潜在机制，以提供创新机制，进一步提高有机-无机杂化卤化物钙钛矿的光伏功能。该项目计划实现三个关键目标：(i) 揭示掺杂可调 SOC 的创新机制，(ii) 通过 Rashba 效应探索 SOC 对直接/间接能带跃迁的影响，以及 (iii) 阐明 SOC 对暗自旋混合的影响混合卤化物钙钛矿的明亮状态，范围从 3D 到 2D 设计。拟议的研究将通过整合材料加工、器件工程和实验测量三个主要跨学科工作来进行，以探索 SOC 效应。材料加工工作将制备具有不同极化和结构对称/不对称性的 3D 和 2D 钙钛矿，为探索 SOC 效应提供基础平台。该设备工程工作将制备从 3D 到 2D 结构的最先进的钙钛矿太阳能电池。实验测量将包括磁场效应、光偏振调制光电流/光致发光、时间分辨光致发光光谱和泵浦探针瞬态吸收，以揭示在引入掺杂后控制从 3D 到 2D 设计的混合卤化物钙钛矿中 SOC 效应的潜在机制、结构排序和外部刺激。总体而言，该项目将阐明控制 SOC 效应、Rashba 效应和自旋混合的关键因素，以从根本上推进钙钛矿光伏器件。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进行评估，被认为值得支持审查标准。

项目成果

Enabling Self-passivation by Attaching Small Grains on Surfaces of Large Grains toward HighPerformance Perovskite LEDs

通过在大颗粒表面附着小颗粒实现高性能钙钛矿 LED 的自钝化

• DOI: doi:10.1016/j.isci.2019.07.044
• 发表时间: 2019-09
• 期刊: iScience
• 影响因子: 5.8
• 作者: Qin; Jiajun
• 通讯作者: Jiajun

Tuning spin-orbit coupling towards enhancing photocurrent in hybrid organic-inorganic perovskites by using mixed organic cations

通过使用混合有机阳离子调整自旋轨道耦合以增强杂化有机-无机钙钛矿中的光电流

• DOI: 10.1016/j.orgel.2020.105671
• 发表时间: 2020-06-01
• 期刊: Organic Electronics
• 影响因子: 3.2
• 作者: Yixuan Dou;Hengxing Xu;Yongtao Liu;Miaosheng Wang;Jia Zhang;O. Ovchinnikova;Bin Hu
• 通讯作者: Bin Hu

Polarization effects of transition dipoles on photoluminescence and photocurrent in organic-inorganic hybrid perovskites

过渡偶极子的偏振效应对有机-无机杂化钙钛矿光致发光和光电流的影响

• DOI: 10.1016/j.nanoen.2019.104004
• 发表时间: 2019-11-01
• 期刊: Nano Energy
• 影响因子: 17.6
• 作者: Shengbo Ma;Hengxing Xu;Miaosheng Wang;Jiajun Qin;Ting Wu;Ping Chen;Bin Hu
• 通讯作者: Bin Hu

Two‐Photon Up‐Conversion Photoluminescence Realized through Spatially Extended Gap States in Quasi‐2D Perovskite Films

通过准二维钙钛矿薄膜中空间延伸的间隙态实现双光子向上转换光致发光

• DOI: 10.1002/adma.201901240
• 发表时间: 2019-10-23
• 期刊: Advanced Materials
• 影响因子: 29.4
• 作者: Xixiang Zhu;Hengxing Xu;Yongtao Liu;Jia Zhang;Miaosheng Wang;I. Ivanov;O. Ovchinnikova;Bin Hu
• 通讯作者: Bin Hu

Uniform Permutation of Quasi-2D Perovskites by Vacuum Poling for Efficient, High-Fill-Factor Solar Cells

通过真空极化均匀排列准二维钙钛矿，用于高效、高填充因子太阳能电池

• DOI: 10.1016/j.joule.2019.09.020
• 发表时间: 2019-12-18
• 期刊: Joule
• 影响因子: 39.8
• 作者: Jia Zhang;Jiajun Qin;Miaosheng Wang;Yujie Bai;Hanfeng Zou;J. Keum;Runming Tao;Hengxing Xu
• 通讯作者: Hengxing Xu