Conjugated Energy Transport and Hot Carrier Diffusion in 2D Transition Metal Dichalcogenides: Novel Characterization toward Fundamental Understanding

二维过渡金属二硫属化物中的共轭能量传输和热载流子扩散：通向基本理解的新表征

• 批准号: 1930866
• 负责人: Xinwei Wang
• 金额: $ 33.77万
• 依托单位: Iowa State University
• 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=1930866&HistoricalAwards=false
• 关键词: Conjugated; Energy; Transport; Hot; Carrier

Two-dimensional transition metal dichalcogenides (TMDs) are materials that have an extremely small thickness (down to a few atoms level). They have broad applications including flexible circuits, sensors, and low power transistors. Their thermophysical properties and energy transport capability directly determine their performance and durability. Also, their electron transfer rate is a property that directly determines device functionality. This project uses ultrafast lasers and a continuous laser to excite and probe the molecular vibrations modes (Raman spectroscopic signal) of TMDs, and use such signals to distinguish and characterize the thermophysical properties, electron transfer rate, and interface energy transfer capability. The outcome of the project should establish the critical knowledge base needed in TMDs structure tailoring, device design, and thermal optimization. Furthermore, the project integrates research activities into education via classroom teaching and new class module development, fosters minority student research training, and stimulates research interests of K-12 students by various outreach activities including science fair, lab tour, and providing high-school teacher research experience.The goals of this project are to conduct further deployment of a novel energy transport state-resolved Raman to characterize hot carrier diffusivity, phonon thermal conductivity, interface thermal resistance for supported TMDs, and electron-hole nonradiative recombination coefficient for monolayered TMDs. The project investigates the effect of physical structure on the three transport processes: hot carrier diffustion, in-plane phonon transport, and cross-interface energy transport (for supported TMDs), studies the effect of substrate on properties, and explores the effect of temperature (70 K to 850 K) on properties as well. This represents the first and high precision consideration of hot carrier transport and radiative electron-hole recombination in 2D materials. This project significantly promotes the field of defect engineering in 2D TMDs, and provides frontier perspective on the challenges and opportunities in this emerging field.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.

二维过渡金属二硫属化物 (TMD) 是厚度极薄（低至几个原子水平）的材料。它们具有广泛的应用，包括柔性电路、传感器和低功率晶体管。它们的热物理特性和能量传输能力直接决定了它们的性能和耐用性。此外，它们的电子传输速率是直接决定设备功能的属性。该项目利用超快激光器和连续激光器来激发和探测TMD的分子振动模式（拉曼光谱信号），并利用这些信号来区分和表征热物理性质、电子传递速率和界面能量传递能力。该项目的成果应建立 TMD 结构定制、器件设计和热优化所需的关键知识库。此外，该项目通过课堂教学和新课程模块开发将研究活动融入教育，促进少数民族学生的研究培训，并通过科学博览会、实验室参观和提供高中教师等各种外展活动激发K-12学生的研究兴趣该项目的目标是进一步部署一种新型能量传输状态分辨拉曼来表征热载流子扩散率、声子热导率、支撑TMD的界面热阻以及电子空穴非辐射复合系数单层TMD。该项目研究了物理结构对三种传输过程的影响：热载流子扩散、面内声子传输和跨界面能量传输（对于支持的TMD），研究基材对性能的影响，并探索温度的影响（70 K 至 850 K）也适用于属性。这代表了二维材料中热载流子传输和辐射电子空穴复合的首次高精度考虑。该项目极大地促进了二维 TMD 缺陷工程领域的发展，并为这一新兴领域的挑战和机遇提供了前沿视角。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

Distinguishing Optical and Acoustic Phonon Temperatures and Their Energy Coupling Factor under Photon Excitation in nm 2D Materials

• DOI: 10.1002/advs.202000097
• 发表时间: 2020-05-26
• 期刊: ADVANCED SCIENCE
• 影响因子: 15.1
• 作者: Wang, Ridong;Zobeiri, Hamidreza;Yue, Yanan
• 通讯作者: Yue, Yanan

THERMAL CONDUCTIVITY ENHANCEMENT OF POLYMERS VIA STRUCTURE TAILORING

• DOI: 10.1615/jenhheattransf.2020034592
• 发表时间: 2020
• 期刊: Journal of Enhanced Heat Transfer
• 影响因子: 2.3
• 作者: Shen Xu;Jing Liu;Xinwei Wang

Robust and high-sensitivity thermal probing at the nanoscale based on resonance Raman ratio (R3)

• DOI: 10.1088/2631-7990/ac6cb1
• 发表时间: 2022-09-01
• 期刊: INTERNATIONAL JOURNAL OF EXTREME MANUFACTURING
• 影响因子: 14.7
• 作者: Zobeiri, Hamidreza;Hunter, Nicholas;Wang, Xinwei
• 通讯作者: Wang, Xinwei

Ultra-high thermal sensitivity of graphene microfiber

• DOI: 10.1016/j.carbon.2022.12.013
• 发表时间: 2022-12-12
• 期刊: CARBON
• 影响因子: 10.9
• 作者: Lin, Huan;Hunter, Nicholas;Wang, Xinwei
• 通讯作者: Wang, Xinwei

Determination of a Raman shift laser power coefficient based on cross correlation

基于互相关的拉曼位移激光功率系数的确定

• DOI: 10.1364/ol.475008
• 发表时间: 2022
• 期刊: Optics Letters
• 影响因子: 3.6
• 作者: Hunter, Nicholas;Rahbar, Mahya;Wang, Ridong;Mahjouri-Samani, Masoud;Wang, Xinwei
• 通讯作者: Wang, Xinwei