The current work describes an attempt to synthesize hybrid materials combining porous aromatic frameworks (PAFs) and dendrimers and use them to obtain novel highly active and selective palladium catalysts. PAFs are carbon porous materials with rigid aromatic structure and high stability, and the dendrimers are macromolecules which can effectively stabilize metal nanoparticles and tune their activity in catalytic reactions. Two porous aromatic frameworks, PAF-20 and PAF-30, are modified step-by-step with diethanolamine and hydroxyl groups at the ends of which are replaced by new diethanolamine molecules. Then, palladium nanoparticles are applied to the synthesized materials. Properties of the obtained materials and catalysts are investigated using X-ray photoelectron spectroscopy, transmission electron microscopy, solid state nuclear magnetic resonance spectroscopy, low temperature N₂ adsorption and elemental analysis. The resulting catalysts are successfully applied as an efficient and recyclable catalyst for selective hydrogenation of alkynes to alkenes at very high (up to 90,000) substrate/Pd ratios.

Bifunctional catalysts are a major type of heterogeneous catalytic systems that have been widely investigated for biomass upgrading. In this work, Ru-catalysts based on sulfonated porous aromatic frameworks (PAFs) were used in the hydrodeoxygenation (HDO) of lignin-derived compounds: guaiacol, veratrole, and catechol. The relationship between the activity of metal nanoparticles and the content of acid sites in synthesized catalysts was studied. Herein, their synergy was demonstrated in the Ru-PAF-30-SO₃H/5-COD catalyst. The results revealed that this catalytic system promoted partial hydrogenation of lignin-based compounds to ketones without any further transformations. The design of the Ru-PAF-30-SO₃H/5-COD catalytic system opens a promising route to the selective conversion of lignin model compounds to cyclohexanone.

A platinum catalyst and a ruthenium catalyst were synthesized from a porous aromatic framework, namely PAF-30. The catalyst properties were examined in hydrogenation of phenol and guaiacol at 80–250°C and at a hydrogen pressure of 30 atm in the presence of various solvents. Significant effects of the reaction medium, process conditions, and catalyst morphology on the reaction mechanism were demonstrated. Reaction conditions optimal for complete conversion of phenol and guaiacol to hydrogenation products were selected for both catalysts.

High-temperature proton exchange membrane systems (HT-PEM) based on polybenzimidazole (PBI) membranes are a promising technology offering significant advantages over their low-temperature counterparts. A key challenge limiting its long-term durability is the leaching of phosphoric acid (PA) from the membrane during operation. This work introduces, for the first time, the strategy of modifying polybenzimidazole (PBI) membranes with amino-functionalized porous aromatic frameworks (PAF-20-NH₂) to fundamentally enhance their PA retention and operational stability, a critical challenge for high-temperature PEM technologies. We propose that the synergistic combination of the framework’s nanoscale porosity and the specific interaction of its amino groups create an unprecedented network for acid immobilization via reinforced hydrogen bonding. A comprehensive study of the membranes’ physicochemical and structural properties reveals that PAF-20-NH₂ modification results in a significant and quantitatively demonstrated improvement in acid retention capacity, directly translating into a notable increase in proton conductivity compared to both pristine PBI and membranes modified with the non-functionalized PAF-20. These findings establish a new, highly effective pathway for the rational design of next-generation high-performance PBI-based membranes.

This paper reports on an investigation of the alkylation of guaiacol with isopropanol and cyclohexanol over sulfonated porous aromatic frameworks, designated as PAF-20–SO₃H and PAF-30–SO₃H. The catalyst structures were characterized by infrared spectroscopy and low-temperature nitrogen adsorption; the elemental composition and acidity were measured by CHNS analysis and potentiometric titration. The alkylate composition was found to be sensitive to the reaction conditions and catalyst structure. PAF-30–SO₃H was demonstrated to achieve 58% guaiacol conversion over 2 h of alkylation with cyclohexanol at 250°C and 3 MPa, with the reaction products mostly consisting of benzene ring monoalkylation products. In guaiacol alkylation with isopropanol, the product composition depends on the catalyst structure: after 6 h of reaction, the benzene ring monoalkylation products prevailed (accounting for up to 23% of the total product) in the case of PAF-20–SO₃H, whereas PAF-30–SO₃H promoted the yield of a mixture of monoalkylates (up to 34%) and dialkylates (up to 35%).

Amino-containing porous aromatic frameworks, designated as PAF-20–NH ₂ -pre/post and PAF-30–NH ₂ -pre/post , were synthesized using a combination of pre- and post-modification, and were then used to prepare a number of Pd catalysts with various metal concentrations. The activity of the catalysts was tested in selective hydrogenation of a series of alkynes and dienes at 60°C and 10 atm hydrogen pressure. The effects of the modification technique and palladium content on the morphology and catalytic activity of nanoparticles were investigated, and the reaction patterns were identified for each substrate type. The reusability of the catalysts over at least six reaction cycles was demonstrated.