Synthesis and characterization of silicalite powders and membranes with micro–meso bimodal pores

Designing hierarchical porous features of ZSM-5 zeolites via Si/Al ratio and their dynamic behavior in seawater ion complexes

“…However the 0.36 nm zeolite micropore size is considerably smaller than that previous reported for MFI zeolites (containing no cations from synthesis) by PALS (0.55 nm±0.03 nm) [32], by low pressure N 2 adsorption (0.54 nm) [33] or by crystallography for the 10-member ring openings (0.56 nm) [6,30]. 0.36 nm measured in this work could be an average of the accessible intracrystalline spaces as the positrons can access both the 0.55 nm pores and the smaller surrounding chambers within the MFI lattice.…”

Bimodal micro‐mesoporous aluminosilicates for heavy oil cracking: Porosity tuning and catalytic properties

“…It has been recognized that hierarchical pore structure that combines the advantages of both mesoporous materials and microporous zeolites can offer attractive features and circumvent the problems aforementioned. 9,10 There have been several successful examples regarding the synthesis of such hierarchical porous materials, such as by compositing mesoporous materials with zeolites 11,12 and by creating mesoporosity in zeolite crystals. 13,14 Nevertheless, the diffusion path length in the micropore channels of these composite materials is still quite long for diffusion-limited reactions, 15 because of the bulky and separate nature of microporous zeolites in these composite materials.…”

Surface roughness and chemical properties of porous inorganic films

“…100-200 nm diameter, as confirmed by SEM showed in Fig. 5a) is initially deposited [12,17] on the surface of silicon wafer. The surface morphology as determined by SEM is consistent with individual particles packing on the surface.…”

“…The free-standing films were calcined under the same conditions as done for the spin-coated films before these characterizations. Figure 1 shows XRD patterns of silicalite, γ-alumina, mesoporous YSZ and macroporous YSZ films, which exhibit deflection peaks characteristic of MFI type structure for silicalite [12] and cubic phases for γ-alumina and YSZ [9][10][11]. The XRD spectrum with long-range crystallinity for silicalite film is consistent with randomly oriented MFI type zeolite.…”