Selective control of cubic and hexagonal mesophases for titania and silica thin films with spin-coating

Controllability of pore size on macroporous sol-gel silica films embedding rhodamine 6G

“…Thus, at 1800 rpm the pores shown a reduced diameter in comparison to these at 900 rpm, as shown in Figure . 4. This behavior is similar to the reported by Pan and Lee (2005), where authors control the pore morphology by varying spin coating speed.…”

Mesoporous TiO2 Thin Films: State of the Art

“…The evaporation process during the aging period after the spin-or dip-coating deposition plays a critical role not only for the formation of ordered porosity but also to direct the symmetry displayed by the pore arrays [21]. During the last decade, many research groups have reported the effects of the aging conditions onto the mesostructure of titania thin films, and they confirmed that high humidity conditions are a requisite to access highly ordered mesostructure in titania thin films [29,43,44].…”

“…Owe to interfacial orientation preferences between the substrate and the material, the 2D hexagonal mesoporous thin films present their pore channels parallel to the surface [25]. For this reason, many research groups have struggled to synthesize cubic mesoporous thin films, which present, regardless of the orientation, pore openings from their surfaces owe to their intrinsic geometry [44,[49][50][51][52][53]. Often, the solution resides in the optimization of the composition of the precursor solution performed by varying the ratios between quantity of surfactant and inorganic precursor [25,54,55].…”

“…In Figure 6 an XRD pattern of a dense anatase TiO 2 thin film deposited on a glass substrate is reported [60], clearly showing the broadening of the background level due to the halo generated by the amorphous support. A small-angle diffraction pattern, instead, could reveal the eventual presence of an ordered array of mesopores within the MTTFs, allowing the determination of its geometry, i.e., cubic lamellar or hexagonal [44,62], as shown in Figure 7. Mesoporous TiO 2 Thin Films: State of the Art http://dx.doi.org/ 10.5772/intechopen.74244…”

Molecularly imprinted La-doped mesoporous titania films with hydrolytic properties toward organophosphate pesticides

“…20 Porous materials, in particular mesoporous materials, whose porosity falls within the 2-50 nm range, represent an alternative to organic polymers and, especially in the form of hybrid organic-inorganic frameworks, have recently attracted the attention of the scientific community for their broad applicability. [21][22][23][24] Moreover, recent developments in this class of materials range from photoelectrochemical applications 25 to water decontamination. 26 The use of mesoporous materials for molecular imprinting offers several intrinsic advantages, such as an easier removal of the molecular template, a higher binding capability and enhanced diffusion properties.…”