CAREER: Investigation of strain and superior functionalization schemes for large enhancement of thermal conductivity in polymer-graphene nanocomposites and binary semiconductors

职业：研究应变和卓越的功能化方案，以大幅提高聚合物-石墨烯纳米复合材料和二元半导体的导热性

• 批准号: 1847129
• 负责人: Jivtesh Garg
• 金额: $ 50万
• 依托单位: University of Oklahoma Norman Campus
• 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: 2019-02-15 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1847129&HistoricalAwards=false
• 关键词: CAREER; Investigation; strain; superior; functionalization

High thermal conductivity polymers and semiconductors hold potential to significantly improve thermal management in wide range of applications including electronics, automobiles, aerospace, power generation and energy harvesting. The research objective of this project is to investigate ways to significantly enhance thermal conductivity of polymer-semiconductor composite materials, through superior bonding between polymer and graphene with higher interfacial thermal transport and by controlling orientation of polymer chains and graphene nanoplatelets. The educational objectives of the project are to engage high school students through a summer camp program. To stimulate fascination with thermal transport, high school students will measure thermal response in different nanocomposites through colorful visualization of temperatures maps using infra-red imaging. Simultaneously the program will aim to enhance diversity by engaging Native American students from various tribal colleges in Oklahoma. The participants will develop understanding of both atomistic simulations and also perform experimental characterization of thermal transport. Within polymers, thermal conductivity is highest along the polymer chain axis. Simultaneous alignment of polymer chains and planar direction of nanoplatelets, to conduct heat along the most efficient directions in the two components, is achieved in this project through strain. Alignment is characterized through microscopy and imaging. Non-equilibrium Green?s function technique has been used to reveal covalent bonding schemes enabling superior phonon transmission between polymer and graphene. Functionalized polymer composites prepared through such schemes are thermally characterized in this work through both experiments and atomistic simulations. Energy gap in the vibrational spectra of semiconductors has been shown to suppress scattering of low energy phonons, leading to large enhancement in their lifetimes, and overall material thermal conductivity. Strain can further increase energy gap, resulting in higher phonon lifetimes. Strain effects are quantified in this project by deriving interatomic force interactions from density-functional theory and using them with an exact solution of the phonon Boltzmann transport equation to predict thermal conductivity. Design of next generation high thermal conductivity polymers and semiconductors will lead to high impact opportunities for improving thermal management in a wide array of technologies. This award is jointly funded by the Division of Chemical, Bioengineering, Environmental, and Transport Systems in the Directorate of Engineering and the Established Program to Stimulate Competitive Research in the Office of Integrative Activities.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.

高导热率聚合物和半导体具有显着改善电子、汽车、航空航天、发电和能量收集等广泛应用中热管理的潜力。 该项目的研究目标是研究通过聚合物和石墨烯之间的良好结合以及更高的界面热传输以及通过控制聚合物链和石墨烯纳米片的取向来显着提高聚合物-半导体复合材料的导热性的方法。该项目的教育目标是通过夏令营计划吸引高中生。为了激发对热传输的兴趣，高中生将使用红外成像对温度图进行彩色可视化，测量不同纳米复合材料的热响应。同时，该计划旨在通过吸引来自俄克拉荷马州各个部落学院的美国原住民学生来增强多样性。参与者将加深对原子模拟的理解，并进行热传输的实验表征。在聚合物中，沿聚合物链轴的导热率最高。该项目通过应变实现了聚合物链和纳米片平面方向的同时排列，以沿着两个组件中最有效的方向传导热量。通过显微镜和成像来表征对准。非平衡格林函数技术已被用来揭示共价键合方案，从而实现聚合物和石墨烯之间卓越的声子传输。通过这些方案制备的功能化聚合物复合材料在这项工作中通过实验和原子模拟进行了热表征。半导体振动光谱中的能隙已被证明可以抑制低能声子的散射，从而大大提高其寿命和整体材料热导率。应变可以进一步增加能隙，从而延长声子寿命。在该项目中，通过从密度泛函理论导出原子间力相互作用，并将其与声子玻尔兹曼输运方程的精确解结合使用来预测热导率，对应变效应进行了量化。下一代高导热聚合物和半导体的设计将为改善各种技术的热管理带来重大影响的机会。 该奖项由工程局化学、生物工程、环境和运输系统部门以及综合活动办公室促进竞争性研究的既定计划共同资助。该奖项反映了 NSF 的法定使命，并被认为值得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来提供支持。

项目成果

The superior effect of edge functionalization relative to basal plane functionalization of graphene in enhancing the thermal conductivity of polymer–graphene nanocomposites – a combined molecular dynamics and Green's functions study

边缘功能化相对于石墨烯基面功能化在增强聚合物石墨烯纳米复合材料的导热性方面的优越效果——分子动力学和格林函数的结合研究

• DOI: 10.1039/d2cp00146b
• 发表时间: 2022-06
• 期刊: Physical Chemistry Chemical Physics
• 影响因子: 3.3
• 作者: Muthaiah, Rajmohan;Tarannum, Fatema;Danayat, Swapneel;Annam, Roshan Sameer;Nayal, Avinash Singh;Yedukondalu, N.;Garg, Jivtesh
• 通讯作者: Garg, Jivtesh

Hot carrier relaxation and inhibited thermalization in superlattice heterostructures: The potential for phonon management

超晶格异质结构中的热载流子弛豫和抑制热化：声子管理的潜力

• DOI: 10.1063/5.0052600
• 发表时间: 2021-05
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: Esmaielpour, Hamidreza;Durant, Brandon K.;Dorman, Kyle R.;Whiteside, Vincent R.;Garg, Jivtesh;Mishima, Tetsuya D.;Santos, Michael B.;Sellers, Ian R.;Guillemoles, Jean;Suchet, Daniel
• 通讯作者: Suchet, Daniel

Ultrahigh thermal conductivity in hexagonal BC6N- An efficient material for nanoscale thermal management- A first principles study

六方BC6N超高导热率——一种用于纳米级热管理的有效材料——第一原理研究

• DOI: 10.1016/j.commatsci.2021.110773
• 发表时间: 2021-12
• 期刊: Computational Materials Science
• 影响因子: 3.3
• 作者: Muthaiah, Rajmohan;Garg, Jivtesh
• 通讯作者: Garg, Jivtesh

Effect of Alignment on Enhancement of Thermal Conductivity of Polyethylene–Graphene Nanocomposites and Comparison with Effective Medium Theory

取向对聚乙烯-石墨烯纳米复合材料导热性能增强的影响及与有效介质理论的比较

• DOI: 10.3390/nano10071291
• 发表时间: 2020-06-30
• 期刊: Nanomaterials
• 影响因子: 5.3
• 作者: Fatema Tarannum;Rajmohan Muthaiah;R. Annam;Tingting Gu;J. Garg
• 通讯作者: J. Garg

Phonon linewidths in InAs/AlSb superlattices derived from first-principles—application towards quantum well hot carrier solar cells

InAs/AlSb 超晶格中的声子线宽源自量子阱热载流子太阳能电池的第一原理应用

• DOI: 10.1088/1361-6641/ab73f0
• 发表时间: 2020-04
• 期刊: Semiconductor Science and Technology
• 影响因子: 1.9
• 作者: Garg, Jivtesh;Sellers, Ian R
• 通讯作者: Sellers, Ian R