In situ synthesis of zeolitic imidazolate frameworks/carbon nanotube composites with enhanced CO2 adsorption

Abstract

A series of ZIF-8 and hydroxyl-functionalized carbon nanotube (CNT) composites were successfully synthesized by the solvothermal method. The obtained ZIF-8/CNT composites were characterized by XRD, SEM, TGA and N 2 adsorption at 77 K. The contents of ZIF-8 and CNTs in the composites were calculated from thermal analysis data. CO 2 and N 2 adsorption at 273 K on the composites was also investigated and compared. The ZIF-8 particles in the composites exhibit similar crystal structures and morphology to those of pure ZIF-8, but display enhanced thermal stability. The surface areas and pore volumes of the ZIF-8/CNT composites are higher than the values calculated for hypothetical physical mixtures, and the synergetic effect between ZIF-8 and CNTs can be proposed. This phenomenon demonstrates that the incorporation of CNTs into ZIF-8 can facilitate the nucleation and crystallization of ZIF-8. As a result, the composites with an optimal CNT content (3.63 wt%) show improved CO 2 adsorption capacity and higher relative selectivity for CO 2 /N 2 compared with pure ZIF-8.

Mixed-Matrix Membranes with Metal–Organic Framework-Decorated CNT Fillers for Efficient CO2 Separation

“…16 In the previous studies, MOF based composites such as MOF-zeolite, MOF-silica have also been used to fabricate MMMs. [17][18][19] The incorporation of MOF made zeolite or silica more compatible with polymer.…”

Synthesis and characterization of three amino-functionalized metal–organic frameworks based on the 2-aminoterephthalic ligand

“…Notably, the decomposition of Sr-ABDC was at a higher temperature than that observed for ZIF-8, another widely studied MOF material with the decomposition temperature at approximately 380°C. [47][48][49] The weight losses observed in Mg-ABDC and Co-ABDC at temperatures below 100°C are due to the evaporation of surface-adsorbed DMF, methanol and moisture. The decompositions of these frameworks were completed at temperatures of 370°C, 500°C and 575°C for Co-ABDC, Sr-ABDC, Mg-ABDC, respectively.…”

Hybrid metal-organic framework nanomaterials with enhanced carbon dioxide and methane adsorption enthalpy by incorporation of carbon nanotubes

“…The BET SSA decreased dramatically after the incorporation of MWCNTs. This indicates that more defects were formed in the JUC-32 structure after being grown on the MWCNTs decorated with the carboxylic groups [27]. A higher BET SSA was obtained for the MWCNTs@JUC32-2 compared with that of MWCNTs@JUC32-1, which may be caused by the smaller crystal size [27] and more gaps between the different phases and crystals.…”

“…With the advantages of the porosity, the large surface areas and the uniform pore characteristics, these MOF materials have great potential for a variety of applications, such as gas storage, chemical separation, catalysis, sensing and drug delivery [19][20][21][22]. Furthermore, owing to the diversity of metal centres and functional ligands, MOF materials offer the opportunity of developing new types of composite materials that may show enhanced gas storage properties or new behaviour compared with the original MOFs [15,[23][24][25][26][27][28][29][30][31].…”

“…With the advantages of the porosity, the large surface areas and the uniform pore characteristics, these MOF materials have great potential for a variety of applications, such as gas storage, chemical separation, catalysis, sensing and drug delivery [19][20][21][22]. Furthermore, owing to the diversity of metal centres and functional ligands, MOF materials offer the opportunity of developing new types of composite materials that may show enhanced gas storage properties or new behaviour compared with the original MOFs [15,[23][24][25][26][27][28][29][30][31].In our previous work, we synthesised a kind of MOF material, Dy(BTC)(H 2 O)·DMF (named JUC-32, JUC = Jilin University, China)[32], which exhibits excellent thermal stability and high carbon dioxide storage capability. We then successfully used JUC-32-Y (replacing the metal Dy with Y) as the host for a hybrid material, by assembling guest molecules of ammonia borane (AB) materials, which exhibited a dramatic improvement in the hydrogen release kinetics, the lower operational temperature and the purity of the released hydrogen [33].…”