Crystallographic analysis of CO2sorption state in seemingly nonporous molecular crystal of azacalix[4]arene tetramethyl ether exhibiting highly selective CO2uptake

Tsue, Hirohito; Takahashi, Hiroki; Ishibashi, Koichi; Inoue, Rikako; Shimizu, Susumu; Takahashi, Daisuke; Tamura, Rui

doi:10.1039/c1ce06126g

Cited by 41 publications

(31 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cavity in the calixarene molecule participates in this gas absorption phenomenon; therefore, two caixarene molecules facing each other arrange themselves in a special hourglass-shaped lattice. This is also confirmed by the ratio of the gases in the calixarene matrix, i.e., 2:1 for CO 2 and 1:1 for CH 4 [44,45] . Since the exact mechanism of calixarene-gas interaction is not fully understood, many investigations are continuing in this area [46,47].…”

Section: Introductionsupporting

confidence: 74%

“…The proposed mechanism for this unique host-guest interaction was the arrangement of two calixarene molecules in an offset manner, facing each other and giving an hourglass-shaped appearance that thereby resulted in a lattice void, suitable for CO 2 and CH 4 capture. However, the ratio of host-guest for CO 2 is 2:1, whereas it is 1:1 for CH 4 , depending upon the molecular dimensions, which allow them to fit into the calixarene lattice void [41][42][43][44][45]. For this reason, CO 2 and CH 4 gases, irrespective of their diameters, become entrapped in the exposed cavities of CL derivative on the surface of Si and hence reveal less permeability.…”

Section: Gas Permeation Experimentsmentioning

confidence: 99%

See 1 more Smart Citation

Comparison of silica and novel functionalized silica-based cellulose acetate hybrid membranes in gas permeation study

et al. 2015

View full text Add to dashboard Cite

Cellulose acetate (CA) is a widely applied glassy polymer in the preparation of gas separation membranes. In the present study, hybrid membranes were prepared by incorporating silica (Si) and silica functionalized with ptetranitrocalix[4]arene (Si-CL) into the CA matrix, and their gas permeation abilities were explored with regard to CO 2 , N 2 and CH 4 gases. The diffusion-induced phase separation (DIPS) method was adopted to make pure CA, CA/Si, and CA/Si-CL hybrid membranes. The concentration of Si-CL was varied as 10 wt%, 20 wt% and 30 wt% in the hybrid membranes. The analytical techniques employed for membrane characterization were Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), and X ray-diffraction (XRD) analysis. The proper interaction of Si and Si-CL was confirmed by FTIR analysis. However, the homogenous surface textures of CA/Si, and CA/Si-CL hybrid membranes were evaluated through SEM. Furthermore, AFM analysis was performed to examine the surface roughness of these hybrid membranes. The changes in the crystallinity of CA were also examined by XRD analysis after adding Si and Si-CL. Moreover, the tensile strength of the CA/Si hybrid membrane was found to be better than that of CA/Si-CL hybrid membranes. CO 2 , CH 4 and N 2 gases were used for gas permeation experiments at 400 kPa. Among CO 2 and CH 4 gases, the permeability of N 2 was high in CA/Si-CL hybrid membranes, and N 2 /CO 2 selectivity of these membranes was 22.6.

show abstract

Section: Introductionsupporting

confidence: 74%

Section: Gas Permeation Experimentsmentioning

confidence: 99%

Comparison of silica and novel functionalized silica-based cellulose acetate hybrid membranes in gas permeation study

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Because the storage generally uses void spaces interconnected through large open channels between the voids inside the crystal, nonporous or seemingly nonporous materials have received less attention. Over the past decades, nevertheless, due to the potential for selective guest capture and release in a controlled manner there have been attempts to study such materials which include calixarenes (8)(9)(10)(11)(12)(13)(14)(15)(16)(17), 4-phenoxyphenol (18), biconcave molecules (19), tris(5-acetyl-3-thienyl)methane (20), metallocyclic complex (21), clarithromycin (22), and metalorganic frameworks (23,24).…”

mentioning

confidence: 99%

“…However, the crystallographic observation of adsorbed gas adsorbents generally has not been possible due to the poor crystalline order of adsorbents upon removing residual solvent/guest molecules and the high mobility of gases even at low temperatures. Only a limited number of gas-adsorbed single-crystal structures have been determined at low temperatures (16,(28)(29)(30)(31)(32)(33)(34)(35)(36).…”

mentioning

confidence: 99%

High-temperature in situ crystallographic observation of reversible gas sorption in impermeable organic cages

Baek

Moon

Graf

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Crystallographic observation of adsorbed gas molecules is a highly difficult task due to their rapid motion. Here, we report the in situ single-crystal and synchrotron powder X-ray observations of reversible CO 2 sorption processes in an apparently nonporous organic crystal under varying pressures at high temperatures. The host material is formed by hydrogen bond network between 1,3,5-tris-(4-carboxyphenyl)benzene (H 3 BTB) and N,N-dimethylformamide (DMF) and by π-π stacking between the H 3 BTB moieties. The material can be viewed as a well-ordered array of cages, which are tight packed with each other so that the cages are inaccessible from outside. Thus, the host is practically nonporous. Despite the absence of permanent pathways connecting the empty cages, they are permeable to CO 2 at high temperatures due to thermally activated molecular gating, and the weakly confined CO 2 molecules in the cages allow direct detection by in situ single-crystal X-ray diffraction at 323 K. Variable-temperature in situ synchrotron powder X-ray diffraction studies also show that the CO 2 sorption is reversible and driven by temperature increase. Solid-state magic angle spinning NMR defines the interactions of CO 2 with the organic framework and dynamic motion of CO 2 in cages. The reversible sorption is attributed to the dynamic motion of the DMF molecules combined with the axial motions/angular fluctuations of CO 2 (a series of transient opening/closing of compartments enabling CO 2 molecule passage), as revealed from NMR and simulations. This temperature-driven transient molecular gating can store gaseous molecules in ordered arrays toward unique collective properties and release them for ready use.in situ X-ray diffraction | nonporous organic crystalline material | CO 2 sorption G uest capture, storage, and removal in porous materials have been interesting topics in chemistry (1-7). The porosity of solids is one of the important factors determining their potential applications in guest storage. Because the storage generally uses void spaces interconnected through large open channels between the voids inside the crystal, nonporous or seemingly nonporous materials have received less attention. Over the past decades, nevertheless, due to the potential for selective guest capture and release in a controlled manner there have been attempts to study such materials which include calixarenes (8-17), 4-phenoxyphenol (18), biconcave molecules (19), tris(5-acetyl-3-thienyl)methane (20), metallocyclic complex (21), clarithromycin (22), and metalorganic frameworks (23, 24).Single-crystal X-ray diffraction can provide the crucial information on the binding interactions or structural changes of guest molecules within pores (25-27). However, the crystallographic observation of adsorbed gas adsorbents generally has not been possible due to the poor crystalline order of adsorbents upon removing residual solvent/guest molecules and the high mobility of gases even at low temperatures. Only a limited number of gas-adsorbed single-crystal struct...

show abstract

“…CL has the great adsorption for CO 2 gas as compared to other gases (Farrukh et al, 2014b). According to Tsue et al (2012), in the single crystal of calixarene, the thermal motion would open transient window, which welcome the CO 2 molecules to get adsorb there. Whereas Piperzane (PZ) consists of N-H group and according to Rochelle, the chemistry of CO 2 and Piperzene can be explained as CO 2 reacts with piperazine to produce PZ carbamate and protonated PZ.…”

Section: Gas Permeation Experimentsmentioning

confidence: 98%

Fabrication, characterisation and CO2/N2 gas permeance study of novel blended membrane

Farrukh

Minhas

Hussain

et al. 2015

IJGW

View full text Add to dashboard Cite

The CO 2 gas is the primary green house gas, which is the main cause of global warming. To capture CO 2 gas, it is important to study the permeance behaviour of CO 2 and N 2 gases from different membranes. In this work, 5,11,17,23-Tetra-tert-butyl-25,27-bis-(2-piprazinoethyl)-26-dihydroxycalix[4]arene (CLP) was blended into cellulose acetate (CA) membrane to be used for gas permeation. Diffusion induced phase separation (DIPS) method was applied to fabricate membranes. The CA/CLP membranes were fabricated by varying concentration of CLP with respect to CA at 10wt%, 20wt%, 30wt% and 40wt%.The prepared membranes were characterised via Fourier transform infra red (FTIR) spectroscopy, scanning electron microscopy (SEM) and atomic force microscopy (AFM). CO 2 and N 2 gases were used for the gas permeation experiments. The increasing trend was observed in permeance of N 2 gas as compared to CO 2 gas for CA-CLP blended membranes.Fabrication, characterisation and CO 2 /N 2 gas permeance 533

show abstract

Crystallographic analysis of CO₂sorption state in seemingly nonporous molecular crystal of azacalix[4]arene tetramethyl ether exhibiting highly selective CO₂uptake

Cited by 41 publications

References 33 publications

Comparison of silica and novel functionalized silica-based cellulose acetate hybrid membranes in gas permeation study

Comparison of silica and novel functionalized silica-based cellulose acetate hybrid membranes in gas permeation study

High-temperature in situ crystallographic observation of reversible gas sorption in impermeable organic cages

Fabrication, characterisation and CO<SUB align="right">2/N<SUB align="right">2 gas permeance study of novel blended membrane

Contact Info

Product

Resources

About