Fabrication and surface characterisation of c-ZnO loaded TTDMM dendrimer nanocomposites for biological applications

Intra-Crystalline Mesoporous Zeolite [Al,Zr]-Y for Catalytic Cracking

“…26,27 When the spectra of the NaY zeolite was compared with that of the [Al,Zr]-NaY zeolite in detail, some of its characteristic peaks were observed to have shifted, such as that for the symmetric stretching of Si−O−T, which was shifted to a lower wavenumber (from 792.7 to 791.2 cm −1 ). 28 Wavenumbers can be calculated by Hooke's law (eq 1) 29 and are inversely proportional to the masses of the bonded atoms (eq 2). Thus, when a particular T atom is replaced with another of larger mass, the Si−O−T vibration signal will shift to lower wavenumber.…”

“…The coordination state of metal elements around Si can be investigated using 29 Si MAS NMR (as shown in Figure 1(f)). For NaY zeolite, the 29 Si MAS NMR spectrum presented five peaks for Si(0Al), Si(1Al), Si(2Al), Si(3Al), and Si(4Al). The spectrum of the [Al,Zr]-NaY zeolite is slightly different from that of the NaY zeolite, presenting a new peak for Si(2Zr) 33 along with the five characteristic peaks mentioned above.…”

“…3.1.3. 29 Si MAS NMR Analysis of the NaY and [Al,Zr]-NaY Zeolites. The coordination state of metal elements around Si can be investigated using 29 Si MAS NMR (as shown in Figure 1(f)).…”

“…29 Si MAS NMR Analysis of the NaY and [Al,Zr]-NaY Zeolites. The coordination state of metal elements around Si can be investigated using 29 Si MAS NMR (as shown in Figure 1(f)). For NaY zeolite, the 29 Si MAS NMR spectrum presented five peaks for Si(0Al), Si(1Al), Si(2Al), Si(3Al), and Si(4Al).…”

“…A facile, direct, and template-free synthesis of intracrystalline mesoporous zeolite Y involving the introduction of Zr atoms under hydrothermal conditions is proposed for the first time. The presence of mesopores in the product was confirmed by N 2 adsorption−desorption isotherms and transmission electron microscopy, while the results of UV− vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, 29 Si MAS NMR spectroscopy, and Fourier-transform infrared spectroscopy analyses confirmed that Zr atoms were successfully introduced to the zeolite framework. The density functional theory was used hypothesize the origin of the mesopores.…”