CAREER: Superelastic Organic Semiconductors (SOSs): A New Class of Molecular Crystals of Responsive Shape Memory

职业：超弹性有机半导体（SOS）：一类新型响应形状记忆分子晶体

• 批准号: 1941323
• 负责人: Kejie Zhao
• 金额: $ 51.13万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1941323&HistoricalAwards=false
• 关键词: CAREER; Superelastic; Organic; Semiconductors; SOSs

This Faculty Early Career Development (CAREER) grant will promote fundamental understanding of the responsive shape memory effect in a new class of superelastic organic semiconductors (SOSs). The shape memory effect can be illustrated by the ability of a material to remember and recover a programmed shape via thermal and mechanical input. Superelasticity refers to the ability of a material to recover a large amount of mechanical deformation at a given temperature. Superelasticity in organic crystals - through interconvertible phase changes - is a recently discovered materials phenomenon. This discovery will likely breed a new research field on polymorphic engineering of molecular crystals, providing a way of overcoming the intrinsic fragility (brittleness) of organic crystals in deformable electronics. Polymorphism is the ability of a material to exist in more than one crystal structure (ordered molecular arrangement). This award explores the fundamental relationship between those structural states and the functionalities of superelasticity, ferroelasticity, and shape memory. Electronic devices with SOSs as active layers can respond to environmental stimuli without additional circuits and find a variety of applications such as remote sensing, memory devices, and programmable electronics. SOSs are also intriguing when it comes to their mechanically and thermally tunable electrical and optical properties. With the potential to create new forms of electronic and optical devices, it is vital to understand and rationalize the mechanics of superelastic organic semiconductors. This research project will both theoretically and experimentally analyze the deformability and shape memory in organic semiconductors under mechanical and thermal load and further understand the fundamental relationship between the mechanical, thermal, and optoelectronic properties of SOSs. The research will leverage the educational and outreach activities based on new curriculum development integrating data sciences, engineering education for K-12 students through an existing collaboration with Women in Engineering Program at Purdue, and engagement of underrepresented groups in engineering sciences.The specific goal of the research is to understand the mechanics and molecular mechanism of superelasticity, ferroelasticity, and shape memory effect in a new class of organic semiconductors using multi-scale theoretical modeling and experimentation approaches. The research will (i) understand the cooperative molecular mechanism underlying the deformability and shape memory effect in the solid-state molecular crystal, (ii) understand the thermodynamics, kinetics, and stress profiles along the trajectory of the martensitic transition under the thermal and mechanical load, (iii) understand the molecular kinetics and deformation twinning/detwinning in organic crystals responsible for the superelasticity, ferroelasticity, and shape memory effect, and (iv) establish the structure-property relationship by understanding the mechanical, electronic, optical, and thermal properties of SOSs for the use in optoelectronics. Overall, the research project is to address a grand challenge in the fundamental understanding of molecular structures of macroscopic and reversible deformation in response to external stimuli. The fundamental understanding of superelasticity/ferroelasticity in organic crystals will create new knowledge about the martensitic phase transition in solid-state molecules. Such knowledge can open new avenues for rapid, reversible modulation of electronic and optical properties by means of molecular design.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.

这个教师早期职业发展（CAREER）补助金将促进对一类新的超弹性有机半导体（SOS）中的响应形状记忆效应的基本理解。形状记忆效应可以通过材料通过热和机械输入记忆和恢复编程形状的能力来说明。 超弹性是指材料在给定温度下恢复大量机械变形的能力。 有机晶体中的超弹性-通过相互转化相变-是最近发现的材料现象。这一发现将可能孕育出分子晶体多晶型工程的新研究领域，为克服可变形电子学中有机晶体固有的脆性（脆性）提供一种途径。 多晶型现象是材料以一种以上晶体结构（有序分子排列）存在的能力。 该奖项探讨了这些结构状态与超弹性，铁弹性和形状记忆功能之间的基本关系。 具有SOS作为有源层的电子器件可以在没有附加电路的情况下响应环境刺激，并找到各种应用，例如遥感，存储器器件和可编程电子器件。当涉及到它们的机械和热可调的电学和光学特性时，SOS也很有趣。随着创造新形式的电子和光学器件的潜力，理解和合理化超弹性有机半导体的力学至关重要。本研究将从理论和实验两方面分析有机半导体在机械和热载荷下的变形性和形状记忆性，并进一步了解SOS的机械，热和光电性能之间的基本关系。该研究将利用基于新课程开发的教育和推广活动，整合数据科学，通过与普渡大学女性工程项目的现有合作为K-12学生提供工程教育，以及工程科学中代表性不足的群体的参与。研究的具体目标是了解超弹性，铁弹性，和形状记忆效应在一类新的有机半导体使用多尺度的理论建模和实验方法。研究将（i）理解固态分子晶体中变形性和形状记忆效应的协同分子机制，（ii）理解在热和机械载荷下沿着马氏体转变轨迹的热力学，动力学和应力分布，（iii）理解有机晶体中负责超弹性，铁弹性，和形状记忆效应，和（iv）建立结构与性能的关系，通过理解的机械，电子，光学和热性能的SOS用于光电子学。总的来说，该研究项目是为了解决在响应外部刺激的宏观和可逆变形的分子结构的基本理解的巨大挑战。对有机晶体中超弹性/铁弹性的基本理解将创造关于固态分子中马氏体相变的新知识。这些知识可以通过分子设计为电子和光学性质的快速、可逆调制开辟新的途径。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值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

Unraveling Molecular Design Principle of Ferroelasticity in Organic Semiconductor Crystals with Two-Dimensional Brickwork Packing

• DOI: 10.1021/acs.chemmater.2c02534
• 发表时间: 2022-12
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Sang Kyu Park;Hongtao Sun;M. Bernhardt;Kyoungtae Hwang;J. Anthony;K. Zhao;Ying Diao

Molecular Mechanisms of Superelasticity and Ferroelasticity in Organic Semiconductor Crystals

有机半导体晶体超弹性和铁弹性的分子机制

• DOI: 10.1021/acs.chemmater.1c00080
• 发表时间: 2021
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Sun, Hong;Park, Sang Kyu;Diao, Ying;Kvam, Eric P.;Zhao, Kejie
• 通讯作者: Zhao, Kejie