Energy is the key feature in our modern society. As we entered the 21st century the exploitation of gaseous primary energy sources such as natural gas and biogas increases dramatically. To handle, store and purify these gaseous species under mild and safe conditions novel porous materials must be designed and created.[1] Porous Organic Frameworks (POFs) based on strong carbon-carbon covalent bonds display valuable features such as high thermal and chemical robustness and moisture resistance while, at the same time, provide high specific surface area suitable for guest managing and storage.[2] In order to understand how pore chemistry affects adsorptive properties, we developed a family of three-dimensional porous frameworks generated from triphenylmethane building blocks (Triphenylmethane Aromatic Frameworks, TAFs).[3] These building blocks generate and sustain the porous network providing extensive reticulation. Additionally, they bear functional groups on the tertiary carbon atom that are retained during the coupling reaction, specifically a hydrogen atom, a hydroxyl group or an amine group (TAF-H, TAF-OH and TAF-NH2, respectively). This prefunctionalization approach ensures the regular and homogeneous distribution of functional moieties along the pore walls. TAFs display BET surface areas between 1000 and 1400 m2/g and high chemical purity.TAF-NH2 displays strong interactions with carbon dioxide guest molecules: the isosteric heat of adsorption at low coverage (ΔQ) reaches 54 KJ/mol. In-situ 2D 1H-13C heterocorrelated MAS NMR technique allows the direct spectroscopic observation of the intimate spatial relationship between the CO2 molecule and the NH2 groups. TAF-OH displays high affinity for methane (ΔQ = 21 KJ/mol). The intermolecular interactions could be further increased by the generation of Li-alkoxyde groups by post-synthetic modification process that allows to reach a high CH4 binding energy of 25 KJ/mol. Further researches are ongoing to establish how control over pore dimension and density of functional moieties could be exploited to obtain tailored materials for adsorptive applications either of gaseous and vapour species or from solution. References [1] S. Kitagawa, Acc. Chem. Res. 2017, 50, 514-516. [2] S. Bracco, D. Piga, I. Bassanetti, J. Perego, A. Comotti and P. Sozzani, J. Mater. Chem A 2017, 5, 10328-10337. [3] J. Perego, D. Piga, S. Bracco, P. Sozzani and A. Comotti, Chem. Commun. 2018, 54, 9321- 9324.
Perego, J., Piga, D., Bracco, S., Sozzani, P., Comotti, A. (2019). Triphenylmethane Aromatic Frameworks (TAFs): Engineered Pore Chemistry for Targeted Gas Adsorption. In Book of Abstracts.
Triphenylmethane Aromatic Frameworks (TAFs): Engineered Pore Chemistry for Targeted Gas Adsorption
Perego, J
Membro del Collaboration Group
;Bracco, SMembro del Collaboration Group
;Sozzani, PMembro del Collaboration Group
;Comotti, A
2019
Abstract
Energy is the key feature in our modern society. As we entered the 21st century the exploitation of gaseous primary energy sources such as natural gas and biogas increases dramatically. To handle, store and purify these gaseous species under mild and safe conditions novel porous materials must be designed and created.[1] Porous Organic Frameworks (POFs) based on strong carbon-carbon covalent bonds display valuable features such as high thermal and chemical robustness and moisture resistance while, at the same time, provide high specific surface area suitable for guest managing and storage.[2] In order to understand how pore chemistry affects adsorptive properties, we developed a family of three-dimensional porous frameworks generated from triphenylmethane building blocks (Triphenylmethane Aromatic Frameworks, TAFs).[3] These building blocks generate and sustain the porous network providing extensive reticulation. Additionally, they bear functional groups on the tertiary carbon atom that are retained during the coupling reaction, specifically a hydrogen atom, a hydroxyl group or an amine group (TAF-H, TAF-OH and TAF-NH2, respectively). This prefunctionalization approach ensures the regular and homogeneous distribution of functional moieties along the pore walls. TAFs display BET surface areas between 1000 and 1400 m2/g and high chemical purity.TAF-NH2 displays strong interactions with carbon dioxide guest molecules: the isosteric heat of adsorption at low coverage (ΔQ) reaches 54 KJ/mol. In-situ 2D 1H-13C heterocorrelated MAS NMR technique allows the direct spectroscopic observation of the intimate spatial relationship between the CO2 molecule and the NH2 groups. TAF-OH displays high affinity for methane (ΔQ = 21 KJ/mol). The intermolecular interactions could be further increased by the generation of Li-alkoxyde groups by post-synthetic modification process that allows to reach a high CH4 binding energy of 25 KJ/mol. Further researches are ongoing to establish how control over pore dimension and density of functional moieties could be exploited to obtain tailored materials for adsorptive applications either of gaseous and vapour species or from solution. References [1] S. Kitagawa, Acc. Chem. Res. 2017, 50, 514-516. [2] S. Bracco, D. Piga, I. Bassanetti, J. Perego, A. Comotti and P. Sozzani, J. Mater. Chem A 2017, 5, 10328-10337. [3] J. Perego, D. Piga, S. Bracco, P. Sozzani and A. Comotti, Chem. Commun. 2018, 54, 9321- 9324.
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