Tailoring morphological and chemical properties of covalent triazine frameworks for dual CO2 and H2 adsorption
The development of functional porous samples suitable as gas-adsorption materials is a key challenge of modern materials chemistry to face with global warming or issues related to renewable energy-storage solutions. Herein, a set of five Covalent Triazine Frameworks (CTFs) featured by high specific surface area (SSA, up to 3201 m2 g−1) and N content as high as 12.2 wt% have been prepared through a rational synthetic strategy and exploited with respect to their gas uptake properties. Among CTFs from this series, CTF-pDCB/DCIHT (4) combines ideal morphological and chemico-physical properties for CO2 and H2 adsorption. Noteworthy, besides ranking among CTFs with the highest CO2 adsorption capacity reported so far (up to 5.38 mmol g−1 at 273 K and 1 bar), 4 displays a H2 excess uptake at 77 K of 2.84 and 5.0 wt% at 1 and 20 bar, respectively, outperforming all CTF materials and 2D Porous Organic Polymers of the state-of-the-art. © 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd.
Intermolecular interactions between imidazolium- and cholinium-based ionic liquids and lysozyme: Regularities and peculiarities
The intermolecular interactions of imidazolium- and cholinium-based ionic liquids and hen egg-white lysozyme (HEWL) were studied by spectral, thermodynamic, and computational methods. The cholinium- and imidazolium-based ionic liquids: choline chloride [Ch][Cl], choline dihydrogenphosphate [Ch][DHP], choline acetate [Ch][OAc], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4], 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][TfO], 1-butyl-3-methylimidazolium acetate [BMIM][OAc] and 1-butyl-3-methylimidazolium methanesulfonate [BMIM][CH3SO3] were selected. The proton donor and acceptor abilities of ionic liquids were determined based on gas chromatography and solution calorimetry data. The temperature denaturation of HEWL in ionic-liquid solution was observed using capillary differential scanning calorimetry (DSC) and circular dichroism spectroscopy (CD). The interaction of ionic liquids with HEWL at the standard temperature was accessed by monitoring the protein’s fluorescence changes. The effect of the ionic liquid on the stability of the native structure of HEWL strongly depends on the proton acceptor ability of ionic liquids. The denaturation temperature of the native structure HEWL is linearly correlated with the enthalpy of the specific interaction (hydrogen bonding) of methanol and trichloromethane in the studied ionic liquids. At the same time, fluorescence data revealed ionic liquid-specific effects, which depend on both ions in the ionic liquid. Both fluorescence and molecular docking data indicate a lack of strong binding between the studied ionic liquids and HEWL. © 2022 Elsevier B.V.