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Mesoporous materials were synthesized through ionic supramolecular templating for the first time by the scientists at Mobil Oil Research and Development in 1992. However more and more efforts were put into the neutral templating route in recent years due to the limitation of ionic route. In this study, mesoporous hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂ or HA) was synthesized using nonionic block copolymer pluronic F127 (EO₉₉PO₆₅EO₉₉) as template. Two groups of HA samples were prepared by coprecipitation method with different concentrations of the surfactant, which were characterized by means of X-ray diffraction (XRD), small angle XRD, electron microscopes and BJH gas absorption method. It was found that the as-synthesized and calcined samples of the two groups had a typical HA crystal phase, but the particle morphologies and pore size distribution were significantly different, depending on the surfactant concentration used. When a high surfactant concentration (10 g F127/100 g distilled water) was used, the sample obtained consisted of spherical particles (~100 nm in diameter), with a maximum distribution of pore size 58 Å. However, when the F127 concentration was 3 g/100 g distilled water, the sample with rod-like particles (~100–300 nm in length and ~40–50 nm in diameter) could be obtained, and a bimodal pore size distribution at 25.3 Å and 30 Å were also observed in this sample.

This work demonstrates the fabrication of a novel three-dimensional (3D) mesoporous spherical ZnO nanoassembly by soft-chemical approach. XRD analysis revealed the formation of single phase hexagonal wurtzite nanostructure. It has been observed that each nanoassembly (100–600 nm) is comprised of numerous nanocrystals of size about 20 nm. These assemblies are fairly stable, well-defined, discrete and porous. The predominance of mesopores is evident from TEM and porosity measurements. Methylene blue (MB) was used as model dye to investigate the photocatalytic activity of ZnO nanoassemblies. These nanoassemblies have good photocatalytic performance due to its unique porous 3D nanostructure having defects. Furthermore, the ZnO nanoassemblies were also explored for the purification toxic metal ions such as Co²⁺, Ni²⁺, Cu²⁺, Cd²⁺, Pb²⁺, Hg²⁺ and As³⁺ from waste-water.

In this paper, magnetic mesoporous silica nanoparticles (Fe₃O₄–nSiO₂–mSiO₂) were synthesized using trimethylbenzene (TMB) as a swelling agent. These composite nanoparticles have a typical sandwich structure with a magnetic core, a nonporous silica middle layer and an ordered mesoporous silica outer shell. The experimental results indicate that the magnetic mesoporous silica nanoparticles have high specific surface area (510 m²/g), large pore size (3.8 nm) and pore volume (1.04 cm³/g). The thickness and pore structure of the out shell can also be easily tailored by adjusting the reaction conditions. The obtained nanomaterials were characterized by X-ray diffraction, transmission electron microscopy and nitrogen adsorption–desorption measurements.

The present work deals with the synthesis of bi-continuous macro and mesoporous crack-free titania–silica monoliths, with well-defined structural dimensions and high surface area. The work also highlights their potential photocatalytic environmental applications. The highly ordered titania–silica monoliths are synthesized through direct surface template method using organic precursors of silica and titania in the presence of surface directing agents such as pluronic P123 and PEG, under acetic acid medium. The monoliths are synthesized with different Ti/Si ratios to obtain monolithic designs that exhibit better photocatalytic activity for dye degradation. The titania–silica monoliths are characterized using XRD, SEM, EDAX, FT-IR, TG–DTA and BET analysis. The photocatalytic activity of the synthesized monoliths is tested on the photodegradation of a textile dye (acid blue 113). It is observed that the monolith with 7:3 ratio of Ti/Si showed significant photocatalysis behavior in the presence of UV light. The influence of various physico-chemical properties such as, solution pH, photocatalyst dosage, light intensity, dye concentration, effect of oxidants, etc. are analyzed and optimized using a customized photoreactor set-up. Under optimized conditions, the monoliths exhibited superior degradation kinetics, with the dye dissipation complete within 10min of photolysis. The mesoporous catalysts are recoverable and reusable up to four cycles of repeated usage.

Mesoporous silica monoliths are an attractive area of research owing to their high specific surface area, uniform channels and mesoporous size (2–30nm). This paper deals with the direct templating synthesis of a mesoporous worm-like silica monolithic material using F127 — a triblock copolymer, by micro-emulsion technique using trimethyl benzene (TMB), as the solvent. The synthesized silica monolith is characterized using SEM-EDAX, XRD, BET, NMR and FT-IR. The monolith shows an ordered worm-like mesoporous structure with tuneable through pores, an excellent host for the anchoring of chromo-ionophores for the naked-eye metal ion-sensing. The mesoporous monoliths were loaded with 4-dodecyl-6-(2-pyridylazo)-phenol (DPAP) ligand through direct immobilization, thereby acting as solid-state naked-eye colorimetric ion-sensors for the sensing toxic Pb${}^{\mathrm{\text{(II)}}}$ ions at parts-per-billion (ppb) level in various industrial and environmental systems. The influence of various experimental parameters such as solution pH, limiting ligand loading concentration, amount of monolith material, matrix tolerance level, limit of detection and quantification has been studied and optimized.

Mesoporous silica nanoparticles (MSNs) have gained attention worldwide due to their structural versatility for diverse applications in a number of frontier areas of sciences. The intrinsic chemical, textural and structural features of MSNs allow fabricating versatile multifunctional nanosystems. The present review provides an overview of the research progress in artificial and biological production of MSNs, their properties and various applications in cutting edge areas of sciences.

This review focus on the preparation of silica nanoparticles functionalized with porphyrins and related compounds. It is aimed to highlight their features as photosensitizers in the area of photodynamic therapy. In this field, photosensitizers have been covalently and non-covalently linked to silica nanoparticles, in order to study their photophysical and biological properties. Another fascinating scenario for photosensitizer-silica nanoparticles hybrids involves the possibility of including metal cores for conditioning the uptake in the target cells, allowing most of the times the combination of therapies and in certain conditions to facilitate the removal and reutilization of the photosensitizer in environmental applications.

Oxidation of olefins with tert-butyl hydroperoxide (TBHP), tetra-n-butylammonium periodate (TBAP) and potassium peroxomonosulfate (Oxone) in the presence of MCM-41 immobilized meso-tetra-4-carboxyphenylporphyrinatomanganese(III) acetate has been studied. The results of this study show better catalytic performance of the heterogonous catalyst using TBHP as oxidant in comparison with Oxone and TBAP in oxidation of the used olefins with the exception of cyclooctene. However, different order of reactivity of various olefins has been observed in the presence of Oxone and TBHP. In spite of the absence of good electron-withdrawing groups at the periphery of porphyrin ligand, the catalyst was recovered and reused (at least four times) without detectable catalyst leaching or a significant loss of the catalytic efficiency. All results have been obtained in the absence of using excess molar ratios of olefin to the oxidant, commonly employed as a strategy to overcome the instability of metalloporphyrins in oxidative conditions.

This paper presents a synthesis process for preparing mesoporous titanium dioxide materials in the absence of any templates and using inorganic acids as catalysts. Tetrabutyl titanate was used as the precursor at ambient temperature, and four different inorganic acids, i.e., hydrochloric, nitric, sulfuric and phosphoric, were used as catalysts. The as-prepared mesoporous TiO₂ materials were characterized by SEM, XRD and nitrogen adsorption/desorption meas-urements. The influences of different inorganic acids on the properties of TiO₂ were discussed and compared in details. Experiments showed that the inorganic acids have significant effects on the surface area, pore volume, pore size, and pore size distribution of the products. The mesoporous TiO₂ materials catalyzed by phosphoric acid exhibited the largest specific surface area and largest pore volume with narrow pore size distribution. Vacuum and infrared drying methods tested in the process were found to have subtle impact on the structure of the TiO₂ materials prepared.

Mesoporous silica was prepared using tetrathoxysilane (TEOS), cetadecyltrimethylammonium bromide (CTAB), aqueous ammonia, acetone and water as silica source, template agent, precipitator and solvent respectively. Stearic acid and polyvinylpyrrolidone (PVP) were employed as additional templates to tailor the pore size in the resultant porous silica. BET, SAXRD and SEM analyses were used to characterize the surface area, pore size, pore structure, pore regularity and morphology of the sample. BET measurement results showed that PVP could increase the surface area but diminish the pore size while stearic acid could decrease the surface area but enlarge the pore size. SAXRD analysis indicated that more additional template introduction gave rise to less order-structured products. All these various results could be attributed to the differently modified CTAB micelles involving stearic acid and PVP addition.

An array of cobalt nanorods of 10 nm in diameter and 14 nm of rod-to-rod distance was fabricated by electrochemical deposition technique into the pores of a mesoporous silica thin film formed on a Pt-coated Si wafer substrate. The cobalt nanorods are highly crystalline with the fcc structure. The magnetic hysterisis data at 300 K show that Co@silica nanocomposite film has strong magnetization anisotropy. Atomic and magnetic force microscopic data on this film revealed the possibility that each cobalt nanorod in the array can be individually magnetized. The number density of the cobalt nanorods is very high with 6 × 10¹² per in², high enough to develop into a terabit magnetic memory device.

Here we report, for the first time, the synthesis of highly crystalline novel mesoporous carbon/nitrogen (C/N)-codoped TiO₂ (MCNT) using ethylene diamine and carbon tetrachloride as the source for nitrogen and carbon, KIT-6 as the template, and titanium tetraisopropoxide as the TiO₂ source. The obtained material has been unambiguously characterized by various sophisticated techniques. XRD and TEM analysis revealed that the MCNT material possesses highly crystalline 3D structure with a continuous network of mesoporous channels as well as structure corresponding to TiO₂. UV-DRS analysis indicated that light absorption shifted to lower energy and stronger absorption in the visible light region. XPS revealed that C and N were doped effectively and C or N dopants might be present in the chemical environment of Ti–O–N or Ti–O–C. It has been found that the material is highly crystalline and possesses high surface area, pore volume and uniform pore size distribution. Owing to its textural characteristics, it could be useful for various applications, such as photocatalysis, fuel cells, bulky biomolecule adsorption and nanotechnology.

Highly ordered mesoporous tungsten trioxide (WO₃) with high surface area (75 m²/g) and well-defined mesopores were successfully prepared through a hard templating method using a mesoporous silica KIT-6 as a template and (NH₄)₆H₂W₁₂O₄₀ ⋅ xH₂O as a tungsten precursor. Oxidative desulfurization of a model oil with H₂O₂ as the oxidant was carried out at 50°C under atmospheric pressure in order to analyze the catalytic activity. The desulfurization reactions were optimized by various kinds of reaction parameters such as H₂O₂/S molar ratio, reaction temperatures and series of sulfur-containing compounds [dibenzothiophene (DBT), benzothiophene (BT) and 4,6-dimethyl dibenzothiophene (4,6-DMBT)]. Excellent catalytic activity for the removal of the sulfur-containing compounds from the model oil was observed with mesoporous WO₃ catalyst, where the activity was maintained during 5 recycle tests without any regeneration process. The high catalytic activity and durability is mainly attributed to well-defined mesopores and high surface area of mesoporous WO₃ catalyst.

Highly ordered mesoporous antimony-doped tin oxide (ATO) materials, containing different amount of antimony in the range of 0–50mol%, are prepared via a nanoreplication method using a mesoporous silica template. The mesoporous ATO materials thus obtained exhibit high electrical conductivity, high reversible capacity, superior cycle stability and good rate capability as anode materials for lithium-ion batteries, compared to those of pure mesoporous tin oxide. Amongst the ATO materials in this work, the mesoporous ATO material with 10mol% of antimony has highest discharge capacity of 1940mAhg^-1 (charge capacity of 1049) at the 1st cycle, best cycle performance (716mAhg^-1 at 100th cycle) and excellent rate capability, which are probably due to the enhanced electrical conductivity as well as reduced crystalline size.

Developing nonmetal-doped mesoporous TiO₂ is highly attractive for preparing semiconductor visible photocatalyst with high activities. Here, we prepare N/F co-doped mesoporous TiO₂ with high vis-photocatalytic activities by a simple liquid phase deposition process followed by annealing in air using C${}_{16}$TAB as a bi-functional template (forming mesoporous and providing dopants). N₂ adsorption isotherms, low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate the formation of wormhole-like mesoporous structure. Wide-angle XRD and high-resolution TEM demonstrate the presence of anatase TiO₂ mesopore wall. XPS analyses reveal that N is doped into TiO₂ lattice in the forms of substitutional and interstitial N species, and that F is doped into the TiO₂ lattice in the form of interstitial F. The mesopore-forming and doping mechanisms are thoroughly discussed based on the bi-function of C${}_{16}$TAB template. Mesoporous structure results in a high BET surface area of TiO₂. High-concentration nitrogen species in anatase lattice and mesoporous structure remarkably increase the visible absorption of TiO₂. As a result, the reaction rate constant of MB degradation catalyzed by N/F co-doped mesoporous TiO₂ photocatalysts is about 7 times that by P25.

Coupling low-temperature plasma technology with catalysts can significantly enhance air purification efficiency and mitigate the generation of secondary pollutants. In this study, mesoporous $\gamma$-Al₂O₃ supported Mn–Ce–Co ternary oxides were introduced into a widely employed tubular dielectric barrier discharges (DBD) reactor for indoor air purification. The plasma-catalytic degradation of HCHO exhibited the following degradation efficiency order: Mn–Ce–Co/$\gamma$-Al₂O₃$>$ Mn/$\gamma$-Al₂O₃$>$ Mn–Ce/$\gamma$-Al₂O₃$>$ Co/$\gamma$-Al₂O₃$>$$\gamma$-Al₂O₃$>$ Ce/$\gamma$-Al₂O₃$>$ Plasma. When compared to plasma treatment alone, the catalyst resulted in a remarkable 1.8-fold enhancement under conditions of 3.0kV, $25^{\circ }$C, 60% RH. Additionally, the concentrations of the by-products O₃ and NO${}_x$ were significantly reduced by 88.2% and 93.3%, respectively. The synergistic interaction between Mn, Ce and Co oxides facilitated the formation and transportation of surface-reactive oxygen species, thereby contributing to the thorough oxidation of HCHO and organic intermediates during the plasma-catalytic process. Moreover, the high specific surface area offered by mesoporous materials enhanced the adsorption and catalytic activity towards HCHO.

Highly ordered mesoporous iron oxide (α-Fe₂O₃) material has been successfully obtained from mesoporous silica template, KIT-6 (3-D Cubic Ia3d symmetry), through nano-replication method. The mesoporous α-Fe₂O₃ material thus obtained exhibits well-defined mesopores (2.7 nm in diameter), high surface area (148 m²/g), high pore volume (0.47 cm³/g) and crystalline frameworks. The morphology of the mesoporous α-Fe₂O₃ material is very uniform in spherical shape of which the average particle size is about 100 nm in diameter.

Hollow TiO₂ microspheres were successfully fabricated by metal salts with low solubility in ethanol acting as intelligent templates using a simple one-pot solvothermal method. Hollow spheres with large diameter were obtained using CuSO₄⋅5H₂O as templates while small ones were obtained using Sr(NO₃)₂ as templates. It is found that titanium precursor plays an important role for the morphology of samples. Solid TiO₂ microspheres were prepared by using titanium tetrabutoxide (TBT). In contrast, bowl-like hollow microspheres were obtained by using titanium tetrachloride (TiCl₄). Furthermore, the amount of H₂O can stimulate the hydrolysis rate of TiCl₄ to form solid spheres. Compared with solid microspheres, hollow TiO₂ microspheres depending on their interior cavity structure exhibited enhanced photocatalysis efficiency for the UV-light photodegradation of methyl orange. Quantificationally, the apparent photocatalytic degradation pseudo-first-rate constant of the hollow microspheres is 1.25 times of that of the solid ones.

The effect of NiO contents on the microstructure of mesoporous NiO-Gd_0.25Ce_0.75O_2-x (NiO-GDC) composite for intermediate temperature solid oxide fuel cells (IT-SOFC) was investigated. Mesoporous NiO-GDC powders with different NiO contents were synthesized by self-assembly hydrothermal method using tri-block copolymer, Pluronic F127, as a structure directing agent. Grain growth/agglomeration behaviors of NiO particles and changes of mesoporous structure of GDC particles were characterized by microstructural analyses. NiO-GDC powders were composed of GDC nano particles with ordered mesopore inside the particles and octahedral NiO grains with truncated-edges. As the amount of NiO increases, specific area value of mesoporous NiO-GDC was decreased, and the agglomeration/growth behavior of NiO grains was accelerated.

In this paper, hierarchical meso/macroporous aluminas were obtained by using nonionic block copolymer EO₁₀₆PO₇₀EO₁₀₆(F127)/agarose hydrogel as cotemplates. The hierarchical structure was confirmed by SEM, TEM and small-angle X-ray diffraction. The results showed that Al₂O₃ exhibited a hierarchical structure with interconnected replicable macropores reproduced by agarose scaffold and ordered mesopores constructed by F127 with uniform size. The template employed here is easy to prepare, degradable and reproducible, indicating the agarose xerogel as a promising candidate for the fabrication of porous metal oxides.