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Effect of axial molecules and linker length on CO₂ adsorption and selectivity of CAU-8: a combined DFT and GCMC simulation study.

ABSTRACT: Density Functional Theory (DFT) and Grand Canonical Monte Carlo (GCMC) calculations are performed to study the structures and carbon dioxide (CO₂) adsorption properties of the newly designed metal-organic framework based on the CAU-8 (CAU stands for Christian-Albrechts Universität) prototype. In the new MOFs, the 4,4'-benzophenonedicarboxylic acid (H₂BPDC) linker of CAU-8 is substituted by 4,4'-oxalylbis(azanediyl)dibenzoic acid (H₂ODA) and 4,4'-teraphthaloylbis(azanediyl)dibenzoic acid (H₂TDA) containing amide groups (-CO-NH- motif). Furthermore, MgO₆ octahedral chains where dimethyl sulfoxide (DMSO) decorating the axial position bridged two Mg²⁺ ions are considered. The formation energies indicate that modified CAU-8 is thermodynamically stable. The reaction mechanisms between the metal clusters and the linkers to form the materials are also proposed. GCMC calculations show that CO₂ adsorptions and selectivities of Al-based MOFs are better than those of Mg-based MOFs, which is due to DMSO. Amide groups made CO₂ molecules more intensively distributed besides organic linkers. CO₂ uptakes and selectivities of MOFs containing H₂TDA linkers are better in comparison with those of MOFs containing H₂BPDC linkers or H₂ODA linkers.

SUBMITTER: Dang DT

PROVIDER: S-EPMC8697253 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Effect of axial molecules and linker length on CO2 adsorption and selectivity of CAU-8: a combined DFT and GCMC simulation study.

Dang Diem Thi-Xuan DT Hoang Hieu Trung HT Doan Tan Le Hoang TLH Thoai Nam N Kawazoe Yoshiyuki Y Nguyen-Manh Duc D

RSC advances 20210330 21

Density Functional Theory (DFT) and Grand Canonical Monte Carlo (GCMC) calculations are performed to study the structures and carbon dioxide (CO2) adsorption properties of the newly designed metal-organic framework based on the CAU-8 (CAU stands for Christian-Albrechts Universität) prototype. In the new MOFs, the 4,4'-benzophenonedicarboxylic acid (H2BPDC) linker of CAU-8 is substituted by 4,4'-oxalylbis(azanediyl)dibenzoic acid (H2ODA) and 4,4'-teraphthaloylbis( ...[more]

PMID: 35423819

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Effect of axial molecules and linker length on CO₂ adsorption and selectivity of CAU-8: a combined DFT and GCMC simulation study.

Publications

Effect of axial molecules and linker length on CO<sub>2</sub> adsorption and selectivity of CAU-8: a combined DFT and GCMC simulation study.

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