Large anisotropic negative thermal expansion in Cu-TDPAT metalorganic framework:A combined in situ X-ray diffraction and DRIFTS study

作     者：Mehrdad Asgari lia Kochetygov Hassan Abedini Wendy L.Queen Mehrdad Asgari;Ilia Kochetygov;Hassan Abedini;Wendy L.Queen

作者机构：Institut des Sciences et Ingenierie ChimiquesEcole Polytechnique Federale de Lausanne(EPFL)-Valais WallisCH-1951 SionSwitzerland Gas Engineering DepartmentFaculty of PetroleumPetroleum University of Technology(PUT)Ahwaz 61991-71183Iran 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2021年第14卷第2期

页      面：404-410页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：the Swiss National Science Foundation under Grant PYAPP2_160581.M.A.acknowledges the Swiss Commission for Technology and Innovation(CTI)(the SCCER EIP-Efflciency of Industrial Processes)for financial support.We also acknowledge the Swiss-Norwegian Beam Line BM01 at European Synchrotron Radiation Facility(ESRF)for the beamtime allocation and Dr.D m itry Chernyshov Dr.Iurii Dovgaliuk Dr.Olga Trukhina and Mr.Vikram Karve for the assistance on the beamline BM01.M.A.also thanks Dr.Pascal Schouwink for assistance on X-ray diffraction experiments at EPFL Valais 

主　　题：negative thermal expansion metal-organic frameworks Cu-TDPAT in situ diffraction in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) 

摘      要：Cu-TDPAT(H_(6)TDPAT=2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine),a stable nanoporous metal-organic framework with rht topology,has sparked broad interest as an adsorbent for several chemical separation *** this work,in situ synchrotron diffraction experiments followed by sequential LeBail refinements reveal that Cu-TDPAT shows unusually large anisotropic negative thermal expansion(NTE).The PASCal crystallography tool,used to analyze the magnitude of the NTE,reveals an average volumetric thermal expansion coefficientαv=-20.3 MK^(-1).This value is significantly higher than the one reported for Cu-BTC(also known as HKUST-1),which contains the same Cu-paddlewheel building unit,αv=-12 MK^(-1).In situ synchrotron single crystal X-ray diffraction and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)were employed to shed light on the NTE *** these two methods,we were able to elucidate the three main structural motions that are responsible for the NTE *** more pronounced NTE behavior of Cu-TDPAT is attributed to the lower symmetry combined with the more complex ligand structure when compared to *** knowledge obtained in this work is important for understanding the behavior of the adsorbent under transient variable temperature conditions in fixed adsorption beds.