Carbon capture using adsorption processes can significantly mitigate global warming. Mg-MOF-74 is a distinct reticularmaterial amongst other adsorbents owing to its distinguished carbon dioxide adsorption capacity and selectivity under lowpressureapplications, while MIL-100(Fe) has lower CO2adsorption capacity, but extraordinary thermal and hydrostabilityin comparison to many classes of MOFs. In this paper, we present CO2adsorption characteristics of new compounds formedby the incorporation of multi-walled carbon nanotubes (mwcnts) into Mg-MOF-74 and MIL-100(Fe). This was done toimprove the thermal diffusion properties of the base MOFs to enhance their adsorption capacities. The new compositeshave been characterized for degree of crystallinity, and the CO2and N2equilibrium uptake. The real adsorption separationhas been investigated by dynamic breakthrough tests at 297 K and 101. 325. The equilibrium isotherm results showed thatMg-MOF-74 and 0. 25 wt% mwcnt/MIL-100(Fe) (MMC2) have the highest CO2uptake in comparison to the other investigatedcomposites. However, the interesting results obtained from breakthrough tests demonstrate that good improvementsin the CO2adsorption uptake and breakthrough breakpoint over pristine Mg-MOF-74 have been accomplished by adding 1. 5wt% mwcnt to Mg-MOF-74. The improvements of CO2adsorption capacity and breakpoint were about 7. 35 and 8. 03%, respectively. Similarly, the CO2adsorption uptake and breakthrough breakpoint over pristine MIL-100(Fe) are obtained by0. 1 wt% mwcnt/MIL-100(Fe) (MMC1) with improvements of 12. 02 and 9. 21%, respectively.

Multi-walled carbon nanotubes (mwcnt)-doped TiO2 thin films were synthesized by the dip-coating method. The obtained products were characterized by SEM, EDX, XRD, and UV-vis absorption spectroscopy. The XRD patterns showed the presence of anatase phase. Absorption spectrum of mwcnt-doped TiO2 revealed a red shift in the optical absorption edge due to carbon doping. The photocatalytic properties were investigated using methylene blue (MB) degradation under visible light (400-700 nm). mwcnt/TiO2 thin films exhibited significantly higher photocatalytic activity as compared to undoped TiO2 thin films due to reduction of the rate of electron-hole recombination by doping carbon. Photocatalytic activity studies with different light source (white light and blue light) indicated a significant enhancement in photocatalytic removal under white light irradiation.

In this work the coexistence effect of Cloisite 30B and multi-walled carbon nanotubes (mwcnt) on the crystal transformation of the polyvinylidene fluoride (PVDF) matrix is reported. It was found that at a constant rate of 3% (by weight) total modification, a higher percentage of beta crystal was evolved in PVDF matrix as compared with that of 3% (by weight) of each nanomaterial in the whole nanocomposite system. These changes in the crystalline structure were quantitatively and qualitatively studied using FTIR and WXRD techniques, respectively. The FTIR technique confirmed the formation of 80%, 71% and 84% of beta crystal for the three prepared composites. The small-angle X-ray scattering (SAXS) technique revealed a 10-time increase in the d-spacing of the nanoclay in nanocomposites as compared with that in raw nanocaly.The morphology of the nanomaterials and the state of dispersion were investigated using SEM and TEM techniques. The synergism observed was assigned to differences in surface conformations and aspect ratio of the nanomaterials. These nanocomposites ensured formation of beta crystals without any need to apply strain. Meanwhile, the piezoelectric constant (d33) of the hot-pressed samples was found to be zero. To attain piezopyroelectric characteristics, there was a need to cold-drawing, probably by smaller strain which resulted in better mechanical properties and anisotropy of the resulting hybrid nanocomposite.