CAREER: Pushing the Lower Limit of Thermal Conductivity in Layered Materials

事业：突破层状材料导热率的下限

• 批准号: 1943813
• 负责人: Jun Liu
• 金额: $ 51.88万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1943813&HistoricalAwards=false
• 关键词: CAREER; Pushing; Lower; Limit; Thermal

Identifying effective strategies to achieve exceptionally low thermal conductivity in solid-state materials can potentially push the extremes in heat conduction. The proposed project seeks to enable novel thermal control functionalities in disordered, layered materials to be applied in sustainable energy infrastructure, such as energy savings by thermal insulation, energy storage in batteries, energy conversion in thermoelectrics, and thermal management in electronics. The integration of research, education, and outreach programs aims to raise the public awareness of challenges in sustainable energy, and motivate students to pursue appropriate education pathways to STEM occupations. Cinematic 360 Virtual Reality lab tours will be developed to "teleport" online K-12 students into the lab to visualize thermal transport research and its applications in sustainable energy. Teachers will be invited to collaborate and pilot educational activities promoting the importance and challenges in sustainable energy infrastructure. The enhancement of students' preparation for a STEM career will be achieved by a summer program with a particular emphasis on reaching out to female and African-American students.The research goal of this CAREER project is to understand how to suppress vibrational energy transport in anisotropic layered materials by disorder. Precise and reversible control of the degree and inhomogeneity of disorder and thus interlayer spacing are achieved by an electrochemistry process, which inserts ions or molecular chains into the van der Waals gaps of layered crystals. The investigations will focus on a model transition metal dichalcogenide crystal, using complementary state-of-the-art theoretical and experimental approaches. The thermal conductivity of bulk crystals with a controllable amount and type of ions or molecular chains inserted into the gaps will be measured by the time-domain thermoreflectance method. The contribution from different types of vibrational modes to the microscopic thermal transport in these disordered crystals will then be analyzed using a combination of lattice dynamics and molecular dynamics methods. The success of this project will enable the first set of experimental and theoretical studies to elucidate the roles of interlayer spacing and bonding environment on suppressing vibrational energy transport, thereby advancing the current understanding on the microscopic thermal transport mechanisms in anisotropic disordered, layered materials.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.

确定有效的策略以实现固态材料中极低的热导率，可以潜在地推动热传导中的极端。拟议的项目旨在使无序的，分层材料的新型热控制功能能够应用于可持续能源基础设施中，例如热绝缘节省能源，电池中的能量存储，热电学的能量转换以及电子设备中的热管理。研究，教育和外展计划的整合旨在提高公众对可持续能源挑战的认识，并激励学生追求适当的教育途径来实现STEM职业。 Cinematic 360虚拟现实实验室旅行将开发以“传送”在线K-12学生进入实验室，以可视化热运输研究及其在可持续能源中的应用。将邀请教师合作和试点教育活动，以促进可持续能源基础设施的重要性和挑战。夏季计划将通过一个特别强调与女性和非裔美国学生接触的夏季计划来增强学生为STEM职业的准备。该职业项目的研究目标是了解如何抑制疾病中各向异性分层材料中的振动能量运输。通过电化学过程实现了对疾病的程度和不均匀性的精确和可逆控制，因此将离子或分子链插入分层晶体的范德华间隙中。该研究将使用互补的最先进的理论和实验方法来关注模型过渡金属二分法晶体。插入间隙中插入的离子或分子链类型的散装晶体的热导率将通过时域热态型方法来测量。然后将使用晶格动力学和分子动力学方法的组合分析不同类型的振动模式对微观热传输的贡献。该项目的成功将使第一组实验和理论研究能够阐明层间间隔和粘结环境在抑制振动能量运输方面的作用，从而促进当前对微观热障碍中的热量热传输机制的理解，以层次的层次奖励，这些奖项反映了NSF的构建范围。影响审查标准。

项目成果

In-Plane Thermoelectric Properties of Flexible and Room-Temperature-Doped Carbon Nanotube Films

• DOI: 10.1021/acsaem.0c00995
• 发表时间: 2020-07-27
• 期刊: ACS APPLIED ENERGY MATERIALS
• 影响因子: 6.4
• 作者: Chatterjee, Kony;Negi, Ankit;Ghosh, Tushar K.
• 通讯作者: Ghosh, Tushar K.

Molecular dynamics simulation of thermal transport in semicrystalline polyethylene: Roles of strain and the crystalline-amorphous interphase region

• DOI: 10.1063/5.0067999
• 发表时间: 2021-12-08
• 期刊: JOURNAL OF APPLIED PHYSICS
• 影响因子: 3.2
• 作者: He, Jixiong;Liu, Jun
• 通讯作者: Liu, Jun

Size Effects in the Thermal Conductivity of Amorphous Polymers

• DOI: 10.1103/physrevapplied.14.044023
• 发表时间: 2020-10-14
• 期刊: PHYSICAL REVIEW APPLIED
• 影响因子: 4.6
• 作者: Feng, Tianli;He, Jixiong;Shrestha, Som S.
• 通讯作者: Shrestha, Som S.

Molecular Dynamics Simulation of Steady-State Droplet Condensation on A Fiber in Direct Contact Membrane Distillation Settings

• DOI: 10.1016/j.molliq.2022.120736
• 发表时间: 2022-11
• 期刊: Journal of Molecular Liquids
• 影响因子: 6
• 作者: S. Raza;Jixiong He;H. Tafreshi;J. Liu

Evaluating the roles of temperature-dependent eigenvectors in predicting phonon transport properties of anharmonic crystals using normal mode analysis methods

• DOI: 10.1063/5.0053287
• 发表时间: 2021-06
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: Jixiong He;Jun Liu