Impact of synthesis parameters on the formation of defects in HKUST-1
Authors/Creators
- 1. Ruhr-University Bochum
- 2. Karlsruhe Institute of Technology
- 3. Technical University of Munich
Description
Employing various synthetic conditions, such as Cu(NO3)2∙3H2O and Cu(BF4)2∙6H2O as metal sources and different solvents, defect engineered analogues of [Cu3(BTC)2] (HKUST-1; BTC = (BTC = 1,3,5-benzenetricarboxylate) with isophthalate (IP) incorporation (abbreviated as DEMOFs) are synthesised and characterized by PXRD, SEM, IR, TGA, NMR and N2 sorption. Our results show that the usage of Cu(NO3)2∙3H2O as Cu-source for DEMOFs should be carefully analysed, due to guest inclusion that occurs at high concentration of IP. Choice of DMF solvent and Cu(BF4)2∙6H2O turns out to be a superior way towards DEMOFs with IP incorporation up to 25%. UHV-IR spectra recorded upon CO adsorption together with the results from XPS show the generation of coordinatively unsaturated Cu+ sites. The results suggest the presence of two different defect types, e.g. missing linker-type defects as well as missing paddlewheels for high incorporation of IP.