Scanning Transmission Electron Microscopy (STEM) and energy dispersive x-ray spectroscopy study were performed on a Thermo Fischer aberration-corrected Themis Z microscope equipped with SuperX EDX system. The instrument was operated at 300 kV with a probe corrector (CEOS DCOR) corrected up to the fifth order. The electron probe with a convergence angle of 21.4 mrad and current of 100 pA was used. Bright-field (BF) and High-angle annular dark-field (HAADF) images and EDX spectra were acquired using Velox software (Thermo Fischer). MOF samples were placed on Cu TEM grids with holey carbon supporting films as dry powder. Reaction samples were dispersed on the TEM grids in the reaction solvent. Nanoparticle size analysis was carried out using ImageJ software. The reported values correspond to the average value of ca. 100 samples.