Functionalization strategy influences the porosity of amino-containing porous aromatic frameworks and the hydrogenation activity of palladium catalysts synthesized on their basis

Abstract

We investigated the influence of functionalization strategy (post- or pre-) on the structure of amino-modified porous aromatic frameworks (PAF-NH2). Different techniques, such as low-temperature N2 adsorption-desorption, IR spectroscopy and solid-state CP-MAS 13C NMR spectroscopy, were used to characterize the synthesized materials. Palladium catalysts were prepared based on obtained PAF-NH2 supports, characterized by TEM, XPS and elemental analysis and studied in the semihydrogenation of C8-acetylenes and dienes. The results show that the modification approach influences structure of PAF and, therefore, the morphology and distribution of palladium nanoparticles. Post-modified catalysts proved to be more active, while pre-modified ones exhibited enhanced selectivity towards desired olefins and improved stability.