基于金属有机框架的二维负泊松比材料理论设计与调控研究

由于在医学、电子器件和国防等领域有着重要应用，设计和调控具有负泊松比的二维材料成为当前研究的热点。然而，目前二维负泊松比材料的研究还存在诸多问题。就研究方法而言，既缺乏系统性的设计策略又缺乏温度效应的研究；就材料本身而言，广泛研究的二维无机负泊松比材料存在负泊松比低、柔韧性差、功能单一等问题。本项目拟在前期研究二维无机负泊松比材料的基础上，基于金属有机框架（MOF）设计二维负泊松比材料。通过结合第一性原理和分子动力学方法以及高通量计算和机器学习技术，首先研究次级构筑单元（SBU）和拓扑结构构建二维MOF负泊松比材料的设计策略，然后研究二维MOF负泊松比材料的性质并阐明官能团修饰和电场对泊松比的调控机制，最后基于研究数据集揭示SBU、拓扑结构、温度等物化参数与泊松比之间的内在关联。本项目研究结果将为后续设计、预测具有负泊松比的二维材料提供理论依据。

Owing to its important applications in the fields of medicine, electronic devices and national defense, the designing and tuning of two-dimensional materials with negative Poisson's ratio has become a current research hotspot. However, many problems still exist in the research of two-dimensional negative Poisson's ratio materials. In terms of research methods, there lacks the systematic design strategy and the study of temperature effect; From the prospective of material, some defects are observed in the widely studied two-dimensional inorganic negative Poisson's ratio materials, such as low negative Poisson's ratio, poor flexibility, single function and so forth. Based on our previous study of two-dimensional inorganic negative Poisson's ratio materials, this project aims to design two-dimensional negative Poisson's ratio materials through the means of metal organic framework (MOF). By combining the first principle and molecular dynamics simulation, as well as high-throughput computation and machine learning technology, we firstly study the design strategy of constructing two-dimensional MOF negative Poisson's ratio materials via secondary build unit (SBU) and topology. Then we study the properties of two-dimensional MOF negative Poisson's ratio materials and explain the mechanism of functional group modification and electric field tuning for Poisson's ratio. Finally, based on the research data set, we expect to reveal internal correlation (f) between physical and chemical parameters such as SBU, topology, temperature and Poisson's ratio. Hopefully, the research results of this project will provide a theoretical basis for the subsequent design and predict of two-dimensional materials with negative Poisson's ratio.