Mesoporous Hybrid Materials Research Articles

Collaborative adsorption and photocatalytic degradation of high concentration pharmaceutical pollutants in water using a novel dendritic fibrous nano-silica modified with chitosan and UiO-66

This study presents a novel hybrid mesoporous material for degrading drug pollutants in water. The hybrid materials, derived from UiO-66 metal-organic framework and chitosan, coated on nano-silica, showed excellent drug adsorption through hydrogen-bonding interactions and efficient photodegradation of antibiotics. The hybrid material's enhanced conductivity and reduced band gap significantly improved pollution reduction by minimising electron-hole recombination. This allows for more efficient charge transport and better light absorption, boosting the material's ability to break down pollutants. Structural and morphological analyses were conducted using various techniques, including scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Optimising the adsorption-photodegradation process involved investigating pH, catalyst dose, and radiation time. Non-linear optimisation revealed an efficiency exceeding 85 % for 400 mg/L tetracycline and doxycycline, the model antibiotics. The optimal parameters for maximal elimination were determined as pH = 4.3, hybrid mesosphere dose = 4.0 mg/mL, and radiation time = 10 min. Kinetic studies favored pseudo-second-order diffusion models over pseudo-first-order models. The hybrid mesosphere showed sustained efficiency after three cycles and performed well in real aqueous samples, removing over 80 % of each antibiotic. This study demonstrates the potential of the hybrid mesoporous material for removing pharmaceutical pollutants in water systems.

A hybrid mesoporous sheet-like NiCo2O4@P,S,N-doped carbon nano-photocatalyst for efficient synergistic degradation of Congo red: Statistical, DFT and mechanism studies

Here, a hybrid mesoporous sheets-like nano-catalyst was used to investigate the degradation of Congo Red (CR) dye. The photocatalytic efficiency of CR dye degradation was evaluated using a variety of mesoporous hybrid materials containing P,S,N-doped carbon (PC1), Co3O4@P,S,N-doped carbon (PC2), NiO@P,S,N-doped carbon (PC3), and NiCo2O4@P,S,N-doped carbon (PC4) sheet-like. The results indicated that the PC4 nano-catalyst exhibited exceptional efficacy in the photocatalytic degradation of CR dye, achieving a degradation efficiency exceeding 99 %. The results also showed that PC4 possessed a band gap of 1.7 eV. To formulate an effective photodegradation system, Analysis of Variance (ANOVA), a valuable statistical method, was employed to examine how varying pH, PC dose, and irradiation time can improve the photodegradation performance. Influential key parameters, including pH, PC dose, irradiation time, and CR concentration, were optimized through response surface methodology applying a four-factor, three-level Box-Behnken design (BBD). To achieve a 99 % decolorization of CR, the optimum conditions were determined to be pH 3.8, PC dose at 14 mg, irradiation time of 10.2 min, and CR concentration of 14.3 ppm. Kinetic models demonstrated that CR degradation followed pseudo-first-order kinetics. Moreover, band gap comparisons, scavenger analysis, and density functional theory (DFT) were used to discuss the CR degradation mechanism.

Recent Advances Ultra-Porous Drug Nano-Carriers: Synthesis and Targeting Approaches

Mesoporous silica has attracted increasing interest due to the pandemic spreading of the viral infection in recent years. These smart materials have many advantages as high loading capacity, high surface area, and unique morphology making them great materials for smart drug carriers. In this review, I summarized the synthesis of Ultra-Porous Drug Nano-Carriers in recent years. Factors affecting (mesoporous nanoparticles) MSN Synthesis as surfactants, Co-surfactants, and solvents were mentioned in the full description and targeting approaches. Types of silica nanoparticles such as Mesoporous SBA-1 silicas, Mesoporous SBA-2 silicas, and hybrid mesoporous materials are also shown in a detailed manner. Future research efforts are also highlighted for AI-based techniques aimed at more accurate tissue engineering prediction and operation optimization in drug carrier-based processes.

Surfactant-Assisted Synthesis of Mesoporous Metal Phosphonates to Control Surface Properties Including an Opportunity to Organize a Bulky Biphenyl Linker.

A wide variety of properties by the presence of functional organic groups have so far been investigated by using periodic mesoporous organosilica (PMO)-type materials but not yet discussed with surface properties that are controlled through the success in synthesizing analogous non-silica-based hybrid mesoporous materials and subsequent evaluation and/or comparison of their properties. Here, we demonstrated the advance in synthesizing biphenyl group (-Ph-Ph-, also expressed as -2Ph)-containing mesoporous metal phosphonates with a rational understanding of surface properties. Ordered mesoporous films of aluminum and titanium ones (AOP-2Ph and TiOP-2Ph) were fabricated by spin-coating and their powders were recovered by spray-drying with the confined assembly of spherical mesopores. As in the case of PMO-type materials, the possibility to organize a -Ph-Ph- linker at the molecular scale was found in the powder samples of AOP-2Ph and TiOP-2Ph because thick frameworks would give an opportunity to organize the bulky -Ph-Ph- linker as the small-sized domains even around spherical mesopores. Surface properties of AOP-2Ph and TiOP-2Ph were evaluated by using the data of water (H2O) adsorption isotherms and compared with those containing different organic groups. The unique hydrophilicity starting from the hydration of AlO4 units was drastically reduced by the presence of -Ph-Ph- groups with a disappearance of the capillary condensation by the presence of mesopores. In addition, a partial replacement of TiO6 units with AlO4 and/or its hydrated AlO6 species was proposed for decreasing the strong hydrophobicity of TiOP-2Ph. The contact angle over the spin-coated films was also measured by using a droplet of H2O, indicating that the surface of the films, especially TiOP-2Ph, was extremely hydrophilic. Although surface properties at the molecular scale can be evaluated by using molecular H2O vapor during the measurement of H2O adsorption isotherms, the interaction of the H2O cluster (droplet) with the bulk surface seems to be predominated by inorganic moieties.

Fast Microwave-Assisted Synthesis, Calcination and Functionalization of a Silica Mesoporous Nanomaterial: UVM-7.

We report here, for the first time, the use of a solid state microwave source for the synthesis, calcination and functionalization of a UVM-7 based hybrid mesoporous silica material. The synthesis of the UVM-7 material is obtained in 2 min at low power (50 W) by the combination of a microwave irradiation and the atrane route. Moreover, it has been successfully calcined and functionalized in just 13 and 4 min respectively with microwave assisted procedures. A total synthesis comprising each individually optimized step, can be executed in only 4 h including work-up, by contrast to a typical synthesis that comprises several days. Savings higher than one order or magnitude are obtained in time and energy. Our example is a proof of concept of the potential use of solid state microwave generators for the ultrafast on-command preparation of hybrid nanomaterials due to their accurate control and accelerating properties.

Hybrid Materials Based on Imidazo[4,5-b]porphyrins for Catalytic Oxidation of Sulfides

Heterogenized metalloporphyrin catalysts for oxidation reactions are extensively explored to improve chemical production. In this work, manganese meso-tetraarylporphyrins were immobilized on hydrated mesoporous titanium dioxide (SBET = 705 m2 g−1) through carboxylate or phosphonate anchoring groups separated from the macrocycle by the 2-arylimidazole linker fused across one of the pyrrolic rings of the macrocycle. The element composition of two mesoporous hybrid materials thus obtained were investigated and the integrity of the immobilized complexes was shown by different physicochemical methods. Finally, the catalytic efficiency of the more stable material Mn(TMPIP)/TiO2 with the phosphonate anchor was evaluated in the selective oxidation of sulfides to sulfoxides by molecular oxygen in the presence of isobutyraldehyde (IBA). The heterogenized complex has shown excellent catalytic activity exhibiting a turnover (TON) of ~1100 in a single catalytic run of the sulfoxidation of thioanisole. The catalyst was successfully reused in seven consecutive catalytic cycles.

A fluorescence “turn-on” probe for the detection of HSO3− based on a pyrene-functionalized mesoporous silica material

An organic-inorganic hybrid mesoporous material PYA-SBA-15 was developed as a fluorescent probe for HSO3− with high selectivity and sensitivity, which was attributed to the Michael addition reaction between the carbon-nitrogen double bond and HSO3−.

Development of an Efficient Bi-Functional Catalyst made of a Novel Hybrid Material for Rechargeable Zn-Air Battery

One-pot synthesis of mesoporous hybrid material consisting of Mn-Co/CoO nanoparticles encapsulated in an N-doped graphene shell decorated with Mo2C nanoparticles (Mo2C-NC@Mn-Co/CoO) was reported. The Mn and Mo components synergistically refined the graphitized carbons due to the interactions with N and C atoms while promoting the stability of the Co/CoO nanoparticles. These components exhibited a beneficial effect on the dispersion of the active metal/metal oxide nanoparticles and the formation of a mesoporous structure under high-temperature conditions, which together led to optimized oxygen adsorption/desorption capabilities as well as mass transport properties. The hybrid material showed high bifunctional performance for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), as well as promising catalytic properties as the air electrode in a zinc-air battery, featuring superior long-term cycle stability comparable to that of Pt-C/RuO2 materials.

Triazolyl Conjugated (Oligo)Phenothiazines Building Blocks for Hybrid Materials-Synthesis and Electronic Properties.

The Cu-catalyzed alkyne-azide 1,3-dipolar cycloaddition variant provides a highly efficient entry to conjugated triazolyl-substituted (oligo)phenothiazine organosilicon derivatives with luminescence and reversible redox characteristics. Furthermore, by in-situ co-condensation synthesis several representative mesoporous MCM-41 type silica hybrid materials with embedded (oligo)phenothiazines are prepared and characterized with respect to their structural and electronic properties. The hybrid materials also can be oxidized to covalently bound embedded radical cations, which are identified by their UV/Vis absorption signature and EPR signals.

Surface molecular design of organic–inorganic mesoporous hybrid materials for CO2 capture

In the present work, a series of organic–inorganic hybrids was designed by using different solvents on 3-aminopropyltriethoxysilane (APTS) grafting on SBA-15. Different characterization techniques were used to evaluate how distinct solvents drive the surface architecture, amine loading, APTS-SBA-15 linkage configuration, surface area and pore volume. FT-IR and 29Si MAS NMR confirmed APTS grafting on SBA-15 surface. Elemental analysis showed that N loading varied from 2.09% up to 5.21%, while the range of C/N ratios (2.69–4.34) indicated that the number of bonds formed between APTS and SBA-15 (linkage configuration) remained between 2 (C/N = 4.3) and 3 (C/N = 2.6). N2 physisorption and TGA data showed that textural properties and APTS content on the synthesized materials were simultaneously dependent on N loading and linkage configuration. The presented data showed that the hybrids properties can be correlated with the solvent polarity, more specifically with the interaction between the inorganic matrix surface and the solvent during grafting. A new approach was presented using the solvent eluent strength to rationalize such correlation. Among all tested solvents, cyclohexane rendered the adsorbent with the highest N loading (5.21%) and more stable linkage configuration (C/N = 4.34). CO2 capture tests showed that the increase of amine loading and surface density improves not only the hybrid capacity to chemisorb CO2, but also its adsorption efficiency. CO2 capture capacities varied from 25 up to 516 µmol CO2 g−1. The correlation between adsorption capacity and N content for the synthesized APTS-SBA-15 hybrids was best fitted by a power function.

Synthesis, Characterization and Use of Mesoporous Silicas of the Following Types SBA-1, SBA-2, HMM-1 and HMM-2.

Mesoporous silicas have enjoyed great interest among scientists practically from the moment of their discovery thanks to their unique attractive properties. Many types of mesoporous silicas have been described in literature, the most thoroughly MCM-41 and SBA-15 ones. The focus of this review are the methods of syntheses, characterization and use of mesoporous silicas from SBA (Santa Barbara Amorphous) and HMM (Hybrid Mesoporous Materials) groups. The first group is represented by (i) SBA-1 of three-dimensional cubic structure and Pmn symmetry and (ii) SBA-2 of three-dimensional combined hexagonal and cubic structures and P63/mmc symmetry. The HMM group is represented by (i) HMM-1 of two-dimensional hexagonal structure and p6mm symmetry and (ii) HMM-2 of three-dimensional structure and P63/mmc symmetry. The paper provides comprehensive information on the above-mentioned silica materials available so far, also including the data for the silicas modified with metal ions or/and organic functional groups and examples of the materials applications.

Water-Stable, Nonsiliceous Hybrid Materials with Tunable Porosity and Functionality: Bridged Titania-Bisphosphonates

Combining the properties of organic and inorganic moieties with high surface areas and pore volumes offers endless possibilities to design materials adapted to a wide range of advanced applications. The vast majority of mesoporous hybrid materials are siliceous materials, and developing low-cost synthetic methodologies leading to water stable nonsiliceous hybrid materials with controlled texture and functionality is essential. We report here an original strategy for the synthesis of mesoporous bridged titania-bisphosphonate hybrids based on a one-step, templateless nonhydrolytic sol–gel route. The reaction of Ti(OiPr)4 and a rigid bisphosphonate ester in the presence of Ac2O leads to the formation of TiO2 anatase nanorods cross-linked by fully condensed bisphosphonate groups. The porosity can be readily adjusted over a wide range by changing the reaction conditions, and very high specific surface areas (up to 720 m2 g–1) and pore volumes (up to 1.85 cm3 g–1) can be reached. The texture is stable in aqueous media between pH 1 and pH 12. Furthermore, accessible functional organic groups can be easily incorporated using either functional bisphosphonates or easily available monophosphonate compounds. The accessibility of bipyridyl organic groups was checked by Cu2+ adsorption from aqueous solutions. The unique combination of texture, functionality, and stability displayed by bridged titania-bisphosphonates makes these promising materials complementary of other hybrid materials such as organosilicas, MOFs, or mesoporous metal phosphonates.

Bifunctional nitrogen-doped hybrid catalyst based on onion-like carbon and graphitic carbon encapsulated transition metal alloy nanostructure for rechargeable zinc-air battery

We demonstrate a facile approach for the synthesis of bifunctionally active nitrogen-doped mesoporous hybrid material based on onion-like carbon (OLC) and graphitic carbon encapsulated CoFe alloy for the fabrication of rechargeable zinc-air battery (ZAB). The synthetic approach involves controlled temperature annealing of a homogenous mixture of cobalt and iron complexes of hydrolyzed collagen and the subsequent surface engineering by acid treatment. In situ generated CoFe alloy nanoparticle (12.5 nm) catalyzes the growth of OLC. CoFe nanoparticle is encapsulated with multi-layer graphitic carbon shell. The surface-engineered mesoporous catalyst has large surface area (659 m2 g−1) with interconnected mesopores. It is bifunctionally active towards oxygen reduction and oxygen evolution reactions with a potential gap of 0.8 V. It catalyzes oxygen reduction reaction in acidic and alkaline pHs and the kinetics of oxygen reduction in alkaline pH is highly facile with high electron transfer coefficient of 0.95. The Fe-Nx sites of the catalyst actively participate in the oxygen reduction in acidic pH. Rechargeable ZAB is fabricated using the hybrid material based air cathode. It has high open-circuit voltage (1.58 V), peak power density (102 mW/cm2) and remarkable charge-discharge cycling stability. The overall performance is superior to that of the traditional catalyst based ZAB.

Dynamics in Amine-Functionalized Mesoporous Hybrid Materials Probed through Deuterium Magic Angle Spinning NMR and Molecular Dynamic Simulations

We present a deuterium magic angle spinning (MAS) NMR study on two widely used hybrid materials (3-glycidyloxy propyl)trimethoxysilane (3-GPTMS) and 3-(trimethoxysilyl)propyl methacrylate (3-MATMS)...

2D Mesoporous Channels of PMO; a Platform for Cluster-Like Pt Synthesis and Catalytic Activity in Nitrophenol Reduction

Thiourea-bridged organosiloxane is used to synthesize a periodic mesoporous organosilica (PMO). Since this PMO has an S-enriched surface, owing to thiourea functional groups, it exhibits strong coordination toward Pt ions, and it shows a high tunability in the Pt nanoparticles size. This hybrid mesoporous material is employed as a catalyst in the efficient reduction reaction of 4-nitrophenol to 4-aminophenol at room temperature in an aqueous media.

Gelatin-based mesoporous hybrid materials for Hg2+ ions removal from aqueous solutions

High toxicity and bioaccumulation are the two major features that make mercury as the most dangerous heavy metal for the living organisms and mandates its removal from the contaminated water bodies. Keeping this in view, a new gelatin-based mesoporous hybrid material, with SiO2 as the inorganic and gelatin as the biopolymeric component, was synthesized via the sol-gel process. The material was characterized by FTIR, SEM, SEM-EDS, TEM and BET studies. The synthesized hybrid material containing Gelatin/SiO2, has high surface area of 675.92 m2 g−1. It was evaluated as an adsorbent of Hg2+ ions from their aqueous solutions. Parametric study of the factors affecting adsorption process was carried out to find the optimum adsorption conditions. Different kinetic and isotherms models were applied to the data obtained and adsorption was found to follow pseudo-second order kinetics and Langmuir isotherm model. The highest partition coefficient value of 7.13 mg g−1 µM−1 was obtained at the lowest initial Hg2+ ions concentration (50 ppm) studied alongwith an adsorption capacity of 43.85 mg/g while for the highest initial concentration of 225 ppm the respective values were 0.876 mg g−1 µM−1 and 105.075 mg/g. Cumulative adsorption capacity of the hybrid material from reusability studies in seven cycles was found to be 315.6 mg g−1.

Aggregation induced emission active fluorescent sensor for the sensitive detection of Hg2+ based on organic-inorganic hybrid mesoporous material.

We report the preparation of an organic-inorganic hybrid mesoporous material, PHC-SBA-15, derived from the coupling of a pyrene-based derivative PHC and mesoporous SBA-15 silica. Compared with the stable aggregation-induced emission (AIE) properties of PHC, those of PHC-SBA-15 were more promoted and active due to the fixation of PHC and the space limitation in mesoporous SBA-15. The aggregation and disaggregation activities can be tuned by controlling the concentrations in aqueous media and changing the fluorescence color from yellow to blue. In addition to the controllable AIE properties, PHC-SBA-15 was applied for the highly selective and sensitive detection of Hg2+ through the fluorescence quenching of monomeric pyrene in aqueous media. The fluorescence intensity at 395 nm was linearly proportional to that of Hg2+ in the concentration ranges of 0-1.0 × 10-5 and 1.0 × 10-5-10 × 10-5 M, showing a low detection limit of 1.02 × 10-7 M. This work provides an effective strategy for modulating the AIE properties from non-active to active by introducing AIE stable molecule into mesoporous silica material. This method also favors the development of fluorescent sensors for detecting targets with high sensitivity and selectivity in aqueous media with less synthetic difficulties.

Design and synthesis heteropolyacid modified mesoporous hybrid material CNTs@MOF-199 catalyst by different methods for extraction-oxidation desulfurization of model diesel

Abstract The supported catalysts of Mo16V2 loaded with CNTs@MOF-199 are produced via three means including microwave method (CNTs@MOF-199-Mo16V2 (M)), one-pot method (CNTs@MOF-199-Mo16V2 (O)) and impregnation method (CNTs@MOF-199-Mo16V2 (I)), respectively. The structure of the target materials is characterized by means of several analysis methods, and the effect of catalyst on removal of thiophene is investigated with the molecular oxygen as oxidant and the dimethyl formamide (DMF) as extraction solvent. The reaction conditions including catalyst dosage, reaction temperature, oxygen quantity and stirring speed are investigated. The experiment result shows that the catalyst synthesized by one-pot method has the best performance, and the efficiency can reach 100% under the optimum conditions. On the basis of kinetic study, thiophene oxidation shows the kinetic characteristic of a first order reaction, and then rate constant and activation energy were obtained. In addition, response surface design (RSD) is designed and applied to verify the optimum reaction conditions.

Polyacrylonitrile and Hybrid SBA-15: A Robust Composite Material for Use as Copper (II) Adsorbent in Flow Conditions

Novel processes for treating industrial wastewater containing metals are needed nowadays in order to meet environmentally safe water treatment standards. Attention has been paid to innovative adsorbents that permit to trap and subsequently desorb ions, permitting their selective recovery. In this work, we design a robust porous exchange matrix able to adsorb Cu (II) (often found in industrial wastewater), that meets the following requirements: (a) to perform copper desorption with a minimum condition modification, (b) to preconcentrate already desorbed ions, (c) to be reusable, and (d) to be able to work in flow condition. A hybrid mesoporous material matrix (HMM) composed of a hybrid mesoporous filler embedded into a highly accessible polymer was chosen as adsorbent. The mesoporous filler is mesoporous silica (SBA-15) chemically modified through post-grafting with amino groups. The composite material was prepared by combining the adsorbent material and polyacrylonitrile (PAN). The system could be easily processed in columns of fixed bed in order to perform copper adsorption–desorption. Under these conditions, a Cu (II) loading of 1.2 × 10−3 mol per gram of adsorbent material was obtained. Copper desorption was performed in HCl 0.1 M, achieving a final concentration at least 5 times higher than the initial one. The material was reused 10 times without losing its adsorption capacity, demonstrating its potentiality for water treatment.

Amperometric sarcosine biosensor with strong anti-interference capabilities based on mesoporous organic-inorganic hybrid materials

Amperometric enzyme biosensors are some of the simplest and cheapest types of medical devices used in the rapid detection of biomarkers that have been developed in the past fifty years. When the concentrations of biomarkers are at micromoles per liter, such as for sarcosine, which was recently discovered as a biomarker for prostate cancer, the response signal of the interferences is huge, and the biosensor is hard to satisfy the requirements of practical applications. In this manuscript, we describe a strategy for synthesizing a surface electronegative organic-inorganic hybrid mesoporous material, which could reduce the interference signal much better than Nafion and Chitosan. We verify that the surface potential of the carrier nanomaterial plays an important role in excluding anionic interferences. We also prepare a sensitive (16.35 μA mM−1), low LOD (0.13 μM) and wide linear range (1–70 μM) amperometric sarcosine biosensor with excellent anti-interference properties. This mesoporous material provides a bio-composite platform for the development of simple amperometric biosensors for detecting micromoles per liter of analytes in serum or urine.