水滑石剥离能的构效关系挖掘

Structure-activity relationship of exfoliation energy in hydrotalcites

基于层状双金属氢氧化物(水滑石)的插层和二维材料在化工生产中有着重要应用。剥离能是制备水滑石层状材料的关键性能参数,其起源和影响机制仍未有清晰的认知。在本研究中,基于自旋轨道耦合和色散校正的DFT计算系统,研究了不同金属成分水滑石的形成能和剥离能及其特征相关因子。结果表明:水滑石剥离能与石墨烯、hBN和MoS_(2)等二维材料剥离能(18~32 meV/A^(2))相似,不同金属成分的水滑石剥离能在15~50 meV/A^(2)之间。机器学习分析揭示,在层间阴离子确定的前提下,水滑石剥离能与氧八面体容忍因子的倒数呈指数关系。研究结果不仅提供了水滑石剥离能的关键数据,而且揭示了水滑石剥离能与其拓扑结构的相关性,为筛选制备新型水滑石层状材料提供了理论依据和设计原则。

Intercalation and two-dimensional materials based on hydrotalcite(layered double hydroxides,LDHs)have essential applications in chemical production.Exfoliation energy is a crucial parameter for the preparation of hydrotalcite layered materials,and its origin and influence mechanism have not been clearly understood.In this study,we studied the formation and exfoliation energy and their characteristic correlation factors of hydrotalcite based on DFT.The results show that the exfoliation energy of hydrotalcite with different metal compositions is between 15~50 meV/Å^(2),similar to that of two-dimen⁃sional materials such as graphene,hBN,MoS_(2)(18~32 meV/Å^(2)).Analysis by machine learning reveals that the exfoliation energy of hydrotalcite is a linear function of the oxygen octahedral tolerance factor.The results not only provide the exfoliation energy of hydrotalcite,but also reveal the correlation between the exfoliation energy and its topological structure,which provides a theoretical basis for screening and prepar⁃ing new layered materials of hydrotalcite.