CAREER: Chemomechanics of 2D Transition Metal Materials

该学院早期职业发展(CALEAR)项目旨在揭示二维(2D)过渡金属材料的化学反应和力学之间的基本耦合。由于2D过渡金属材料主要是表面，其高度的化学反应活性使其成为环境和健康状况监测的化学和生物传感的理想选择。然而，同样的化学活性性质使得2D过渡金属材料容易受到复杂环境条件的攻击。了解化学-机械耦合对于合成、设计和制造具有弹性的2D过渡金属材料器件至关重要。在这个项目中，将使用先进的实验方法来了解引起这种耦合的潜在机制，这将提高这些材料的性能，并加速它们在工业应用中的集成。教育和外展计划将集中在让学生掌握最先进的2D材料知识和技能。该计划包括让来自奥扎克农村学区的代表性不足的学生参加暑期研究项目，并招募本科生加入研究团队，接触当地医学界。最近开发的原型设备，如2D抗菌过滤器和MXene场效应晶体管将在夏令营计划和外展科学巡演中展示。PI的研究团队将从三个角度实现对2D材料的化学-机械耦合的研究：(1)确定机械应变在影响化学反应活性中的作用；(2)研究化学反应导致的粘合降解；(3)发现化学反应引起的2D过渡金属材料的断裂行为。MoS2(典型的2D过渡金属二卤化物，TMD)和Ti3C2O(典型的2D过渡金属碳化物，MXenes)将作为模板材料，氧化将作为模型化学反应。PI将利用新开发的实验方法来表征化学-机械耦合机制，包括(1)机械应变氧化，(2)原子力显微镜(AFM)结合功能化探针的附着力表征，以及(3)结合化学反应表征的原位扫描电子显微镜(SEM)和透射电子显微镜(TEM)断口实验。原子论建模和基于连续介质力学的理论也将被建立，以使这些特有的化学-机械耦合机制合理化。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审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) project aims to reveal the fundamental coupling between the chemical reactivity and mechanics of two-dimensional (2D) transition metal materials. Being mostly surfaces, the high chemical reactivity of 2D transition metal materials makes them ideal for chemical and biological sensing for environmental and health condition monitoring. However, the same chemically active nature makes 2D transition metal materials vulnerable to attacks from the complex environmental conditions. Understanding the coupled chemo-mechanical coupling is critical in synthesis, design, and fabrication of resilient 2D transition metal material devices. In this project, advanced experimental methods will be used to understand the underlying mechanisms that give rise to this coupling, which will advance the performance of these materials and accelerate their integration in industrial applications. The education and outreach plan will be centered on equipping students with the state of art knowledge and skills in 2D materials. The plan includes participation of underrepresented students from the rural Ozark school districts in the summer research program and recruitment of undergraduate STEM students to join the research team in reaching out to local medical communities. Recently developed prototype devices such as 2D antibacterial filters and MXene field effect transistors will be showcased in the summer camp program and outreach science tours.The PI’s research team will achieve investigate chemo-mechanical coupling in 2D materials from three perspectives: (1) identifying the role of mechanical strain in affecting the chemical reactivity, (2) investigating the chemical reaction induced adhesion degradation, and (3) discovering the fracture behavior of chemically reacted 2D transition metal materials. MoS2 (typical 2D transition metal dichalcogenides, or TMDs) and Ti3C2O (typical 2D transition metal carbides, or MXenes) will be used as the template materials and oxidation will serve as the model chemical reaction. The PI will characterize the chemo-mechanical coupling mechanisms utilizing the newly developed experimental approaches including, (1) mechanically strained oxidation, (2) atomic force microscope (AFM) adhesion characterization with functionalized probe, and (3) in-situ scanning electron microscope (SEM) and transmission electron microscope (TEM) fracture experiments in combination with chemical reaction characterizations. Atomistic modeling and continuum mechanics-based theories will also be established to rationalize these characterized chemo-mechanical coupling mechanisms.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.