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We synthesized high-quality and oriented periodic mesoporous organosilica (PMO) monoliths through a solvent evaporation process using a wide range of mole ratios of the components: 0.17–0.56 1,2-bis(triethoxysilyl)ethane (BTSE): 0.2 cetyltrimethylammonium chloride (CTACl): 0–1.8 × 10 −3 HCl: 0–80 EtOH: 5–400 H 2 O. X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images indicated that the mesoporous channels within the monolith samples were oriented parallel to the flat external surface of the PMO monolith and possessed a hexagonal symmetry lattice ( p 6 mm ). The PMO monolith synthesized from a reactant composition of 0.35 BTSE: 0.2 CTACl: 1.8 × 10 −6 HCl: 10 EtOH: 10 H 2 O had a pore diameter, pore volume, and surface area – obtained from an N 2 sorption isotherm – of 25.0 A, 0.96 cm 3 g −1 and 1231 m 2 g −1 , respectively. After calcination at 280 °C for 2 h in N 2 flow, the PMO monolith retained monolith-shape and mesostructure. Pore diameter and surface area of the calcined PMO monolith sample were 19.8 A, 0.53 cm 3 g −1 and 1368 m 2 g −1 , respectively. We performed 29 Si and 13 C CP MAS NMR spectroscopy experiments to confirm the presence of Si–C bonding within the framework of the PMO monoliths. We investigated the thermal stability of the PMO monoliths through thermogravimetric analysis (TGA). In addition, rare-earth ions (Eu 3+ , Tb 3+ and Tm 3+ ) were doped into the monoliths. Optical properties of those Eu 3+ , Tb 3+ and Tm 3+ -doped PMO monoliths were investigated by photoluminescence (PL) spectra to evaluate their potential applicability as UV sensors.

We report on the effect of inorganic salt on the synthesis of large-pore PMO materials with aromatic groups inside the channel wall. The triblock copolymer template with the aid of inorganic salt could provide a new method to prepare large-pore mesoporous organosilica material with hollow sphere morphology. By adding inorganic salt in reaction mixture, we have successfully controlled ordered structure, morphology, wall thickness, and pore size of PMO with aromatic moieties in the framework.

Highly ordered mesoporous silica, SBA-15 was synthesized using triblock copolymer (P123) as template and tetraethyl orthosilicate (TEOS) as silica source. Through the post-synthesis treatment, pore surface of the mesoporous silica was modified with aminosilane and then Eu3+ ions were incorporated in the modified mesoporous silica for the formation of Eu complex. Mesoporous silica with the hexagonal mesostructure was characterized by small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The successful modification of the mesoporous silica was verified by FT-IR spectra and nitrogen adsorption/desorption isotherms. Eu incorporated mesoporous silicas showed different photoluminescent intensities depending on the pH of acidic and basic aqueous solutions.