A hydrogen-bonded organic framework (HOF), HOF-7, based on a zinc porphyrin-based building block (ZnTDPP) with diaminotriazine moieties has been successfully constructed and structurally characterized (ZnTDPP = 5,10,15,20-tetrakis(4-(2,4-diaminotriazinyl)phenyl)porphyrinato zinc). Single-crystal X-ray diffraction analysis reveals that HOF-7 is built by the 2D layered subunits connected by the intermolecular hydrogen-bonding and π−π interaction, exhibiting two kinds of micropores with sizes of 3.2 × 4.7 Å 2 and 4.2 × 6.7 Å 2 , respectively. This HOF exhibits permanent porosities as demonstrated in the CO 2 sorption and selective adsorption of CO 2 over N 2 .

No abstract

Mesoporous α-iron oxide@graphitized-carbon nitride nanocomposites (α-Fe2O3@g-C3N4-NCs) were synthesized using urea-formaldehyde (UF) resins at 400 °C/2 h. The mesoporous nature of the prepared nanocomposites was observed from electron microscopy and surface area measurements. The electrochemical measurements show the bifunctional nature of mesoporous α-Fe2O3@g-C3N4-NCs in electrolysis of water for oxygen evolution and oxygen reduction reactions (OER/ORR) using 0.5 M KOH. Higher current density of mesoporous α-Fe2O3@g-C3N4-NCs reveals the enhanced electrochemical performance compared to pure Fe2O3 nanoparticles (NPs). The onset potential, over-potential and Tafel slopes of mesoporous α-Fe2O3@g-C3N4-NCs were found lower than that of pure α-Fe2O3-NPs. Rotating disc electrode experiments followed by the K-L equation were used to investigate 4e− redox system. Therefore, the mesoporous α-Fe2O3@g-C3N4-NCs bifunctional electro-catalysts can be considered as potential future low-cost alternatives for Pt/C catalysts, which are currently used in fuel cells.

No abstract

No abstract

Three solvent dependent structures of 2,6-diaminopurine in N,N′-dimethylforamide (DAP-1-DMF), water (DAP-2-H 2 O), and methoxybenzene (DAP-3-CH 3 OC 6 H 5 ) have been structurally characterized. They exhibit different structures because of the different involvement of solvent molecules in the hydrogen bonded frameworks. The DAP molecules tend to be self-assembled with other DAP molecules through hydrogen bonding interactions. DAP has very similar hydrogen bonding interaction patterns to the established DAT group (2,4-diaminotriazinyl), underlying the potential of this new unit for the construction of porous hydrogen bonded organic frameworks.

No abstract

No abstract