Tuning Thermal Expansion in Metal–Organic Frameworks Using a Mixed Linker Solid Solution Approach

• Published in: Journal of the American Chemical Society Vol. 141; no. 32; pp. 12849 - 12854
• Main Authors: Baxter, Samuel J, Schneemann, Andreas, Ready, Austin D, Wijeratne, Pavithra, Wilkinson, Angus P, Burtch, Nicholas C
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 14.08.2019; American Chemical Society (ACS)
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.9b06109

Several metal–organic frameworks are known to display negative thermal expansion (NTE). However, unlike traditional NTE material classes, there have been no reports where the thermal expansion of a MOF has been tuned continuously from negative to positive through the formation of single-phase solid solutions. In the system Zn-DMOF-TM x , Zn2[(bdc)2–2x (TM-bdabco)2x ]­[dabco], the introduction of increasing amounts of TM-bdc, with four methyl groups decorating the benzene dicarboxylate linker, leads to a smooth transition from negative to positive thermal expansion in the a–b plane of this tetragonal material. The temperature at which zero thermal expansion occurs evolves from ∼186 K for the Zn-DMOF parent structure (x = 0) to ∼325 K for Zn-DMOF-TM (x = 1.0). The formation of mixed linker solid solutions is likely a general strategy for the control of thermal expansion in MOFs.