SBA-15 Composites Research Articles

Synergistic enhancement of CO2 capture via amine decorated hierarchical MIL-101(Cr)/SBA-15 composites

Synthesis of amine incorporated hierarchical metal organic framework (MOF) MIL-101(Cr)/SBA-15, meso/micro-porous composites, with tailored properties for CO2 capture is reported. The synthesized composites were characterized in terms of their crystallinity, morphology, functional groups, and textural properties. Isothermal adsorption of CO2 from concentrated sites as well as ambient conditions were evaluated by gravimetric and volumetric measurements. The optimized composite i.e., MIL-101(Cr)/SBA-15/PEI-25 showed improved pseudo-equilibrium adsorption capacity of 3.2 mmol/g at 303 K and 1 bar, compared to nascent SBA-15 (0.8 mmol/g) and the MOF, i.e., MIL-101(Cr) (1.3 mmol/g). Such adsorption performance can be attributed to the basic sites of the impregnated polyethyleneimine (PEI), unsaturated Cr(III) metal sites, and the hierarchical pore structure of the composite which imparts chemical as well physical adsorption forces towards CO2 uptake. Interestingly, lower amine loading of 25 wt% in the composite resulted in facile CO2 desorption at much lower temperature of 65 °C. This guaranteed energy-efficiency and good reusability of the composite, after ten cycles, are evident from their structural and morphological studies.

Hierarchically porous ZSM-5/SBA-15 composite: Tuning pore structure and acidity for hydrodesulfurization of dibenzothiophene

Series ZSM-5/SBA-15 (ZS15-x) composites with different pore structure and acidity were synthesized, and the corresponding NiMo/ZS15-x catalysts were prepared for dibenzothiophene (DBT) hydrodesulfurization (HDS). The controlled introduction of ZSM-5 nanocrystal imparts more acid sites to the NiMo/ZS15 catalyst without altering its fundamental morphology. Furthermore, the increased presence of acid sites enhances the HDS effect of NiMo/ZS15-x catalysts. Simultaneously, the introduction of ZSM-5 nanocrystal modulates the interactions between metal and support (MSI), thereby promoting the dispersion of the active sites. The optimized NiMo/ZS15-50 exhibited superior HDS activities of 98.9 % for DBT, with the optimal reaction rate constant of 3.0 × 10−7 mol/g s−1 and turnover frequency of 2.0 × 10−4 s−1. This can be attributed to its two-dimensional open channels, suitable acidic sites and highly dispersed MoS2. The increased proportion of the ZSM-5 framework and enhanced acidity are advantageous for DBT HDS.

Exploring the potential of ZnO-Ag@AgBr/SBA-15 Z-scheme heterostructure for efficient wastewater treatment: synthesis, characterization, and real-world applications.

This study reports on the synthesis and characterization of ZnO-Ag@AgBr/SBA-15 composites using natural halloysite clay from Yenbai Province, Vietnam, as a silica aluminum source. The synthesized materials demonstrated visible light absorption with a band gap energy range of 2.63-2.98 eV. The dual Z-scheme ZnO-Ag@AgBr/SBA-15 heterojunction exhibited superior catalytic performance compared to ZnO/SBA-15 and Ag@AgBr/SBA-15, owing to its improved electron transfer and reduced electron and hole recombination rate. In particular, the photocatalytic efficiency of ZnO-Ag@AgBr/SBA-15 was evaluated for the removal of harmful phenol red from wastewater under visible light irradiation. The photocatalytic process was optimized by varying the phenol red concentration, pH, and catalyst dosage, and showed that 98.8% of phenol red in 100 mL wastewater (pH = 5.5) can be removed using 40 mg of 20%ZnO-Ag@AgBr/SBA-15 within 120 min. Furthermore, the degradation pathway of phenol red was predicted using liquid chromatographic-mass spectrometry (LC-MS). Finally, the photocatalytic process was successfully tested using water samples collected from the four main domestic waste sources in Hanoi, including the To Lich River, the Hong River, the Hoan Kiem Lake, and the West Lake, demonstrating the high potential of the ZnO-Ag@AgBr/SBA-15 photocatalyst for phenol red degradation in real-world wastewater treatment applications.

Application of Dithiocarbamate Chitosan Modified SBA-15 for Catalytic Reductive Removal of Vanadium(V)

We have successfully synthesized dithiocarbamate chitosan modified SBA-15 (CS2C@SBA) composites, with promise in vanadium (V(V)) elimination. Among the three composites using different mass ratios of dithiocarbamate chitosan to SBA-15, CS2C@SBA−3, which had the highest CS2 substitution, showed the best performance on V(V) removal of which the maximum adsorption capacity could achieve 218.00 mg/g at pH 3.0. The adsorption kinetics were best fitted with a pseudo−second order reaction model, suggesting a chemisorption mechanism. Meanwhile, the Langmuir model fitted better with the adsorption isotherm, revealing a monolayer adsorption behavior. Through FTIR and XPS analysis, the functional group −SH was identified as dominating reduction sites on this composite, which reduced 73.1% of V(V) into V(IV) and V(III). The functional group −NH− was the main adsorption site for vanadium species. This reaction followed a catalytic reduction coupled adsorption mechanism reducing most of V(V) into less toxic vanadium species. Furthermore, CS2C@SBA−3 showed great selectivity towards V(V) in the presence of various co−existing ions in synthetic wastewater and real water samples. Moreover, CS2C@SBA−3 could retain a removal efficiency over 90% after five adsorption−desorption cycles. Based on the aforementioned results, we can conclude that CS2C@SBA−3 has great potential to be applied in efficient remediation of vanadium water−pollution.

Catalytic activity of ratio-dependent SBA-15 supported cerium/Pt catalysts for highly selective oxidation reaction of benzyl alcohol to benzaldehyde

The Pt/Ce bimetal doped Mesoporous SBA-15 with various metal ratios was prepared by a wet chemical route. Several characterization methods were applied to determine the structural and chemical properties of the catalyst such as XRD, FT-IR, SEM, BET, and TEM Analysis. The prepared SBA-15 catalyst has a hexagonal mesoporous structure after the addition of cerium doesn’t affect the structure of the SBA-15 catalyst it is also confirmed by TEM analysis. The catalytic performances of the Pt/Ce-SBA-15 catalysts were examined in the BzOH conversion under acetonitrile as a solvent and tert-butyl hydroperoxide (TBHP) as an oxidant. The Pt/CeO2(15%)-SBA-15 (PCS-15) is the best catalyst composition of the prepared catalyst with a maximum conversion of 98.5% and selectivity of 100%. The reaction parameters like the molar ratio of TBHP: BzOH, catalyst amount, temperature, and reaction time were explored in detail. The recycling studies show that the synthesized Pt/CeO2(15%)-SBA-15 (PCS-15) catalyst is more stable up to 7 consecutive runs. The Pt/CeO2(15%)-SBA-15 composite has tremendous application potential in organic synthesis, fuel cells, and electrochemical biosensors due to its outstanding reactivity, excellent selectivity, and remarkable stability as well as recyclability.

Metals and Antibiotics as Aqueous Sequestration Targets for Magnetic Polyamidoamine-Grafted SBA-15.

In this study, a magnetic generation-5 polyamidoamine (G-5 PAMAM) dendrimer-functionalized SBA-15 (mPSBA) composite was synthesized by coupling amine-functionalized silica (SBA-15-NH2) and amine-functionalized magnetic nanoparticles (MNP-NH2) with the G-5 PAMAM, before characterization and aqueous sorption of As(III), Cd(II), tetracycline, and ciprofloxacin using the composite. The mPSBA characterization data exhibited the typical Si-O-Si infrared peaks from the SBA-15 backbone in addition to the acquired characteristic infrared Fe-O and amide-I/II peaks from the MNP and G-5 PAMAM dendrimers, respectively. Postsorption infrared spectra showing shifts for the amide-linked groups indicated the likely points of contaminant attachment on the composite. Its thermal stability was lower than that of SBA-15 but higher than that of SBA-15-NH, while the XRD diffractograms of the backbone SBA-15-NH and MNP were unchanged in the final composite. The mPSBA composite was a better As(III) and Cd(II) adsorbent than SBA-15 by ≈400 and 140%, respectively, with rapid uptake in the first 60 min and equilibrium achieved at 120 min. Sorption was enhanced with increasing pH (until pHpzc) and initial contaminant concentration. The process was spontaneous and endothermic; thus, increasing ambient temperature enhanced Cd(II) sorption. The sorption data fitted better to the homogeneous fractal pseudo-second-order (FPSO) kinetics model and the Brouers-Sotolongo fractal adsorption isotherm models, indicating complex sorption interactions and pore-filling/contaminant trapping within mPSBA. Further experiments using mPSBA for the uptake of tetracycline and ciprofloxacin showed 679% and 325% higher sorption, respectively, compared with that for SBA-15-NH. In addition to the added advantage of easy removal from solution/treated water after the adsorption process, mPSBA sorption capacities for these studied contaminants [As(III): 23.3 mg/g; Cd(II): 74.5 mg/g; tetracycline: 38.4 mg/g; ciprofloxacin: 23.0 mg/g] are better than those of several advanced adsorbents reported in the literature.

One-Pot Synthesis of CeO2 Modified SBA-15 With No Pore Clogging for NO Reduction by CO

CeO2 modified SBA-15 composites have been prepared by adding cerium precursor (Ce(NO3)3·6H2O) directly into the mixture of soft template (P123), silica precursor (TEOS) and urea aqueous solution but without mineral acid. The products were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), N2 physisorption and transmission electron microscopy (TEM). Results indicated that ceria were successfully grafted onto mesoporous silica matrix and no pore clogging was observed. Both ceria content and mesoporous ordering of the final products were found to depend on urea amount. Compared to CeO2/SBA-15 from conventional impregnation method, the one-pot synthesis not only showed simple and green operation, but also superior catalytic performance in NO+CO reaction after loaded with CuO. It was revealed that both the presence and location of ceria had great influence on the reducibility of CuO, and the catalytic performances were intimately related to the redox properties of crystalline CuO. That is, higher NO conversion and N2 selectivity were achieved over catalyst with easier reduction of crystalline CuO.

Facile Synthesis of Nanoarchitectured Hydrotalcite/SBA-15 Composites for the Efficient Conversion of Levulinic Acid to Ethyl Levulinate

In this work, we report the one-pot fabrication of nanoarchitectured hydrotalcite (HT)/SBA-15 composites via a facile in-situ mesoporous templating approach. The characterization studies conferred that the successful incorporation of HT into the SBA-15 mesopores and the formation of composites. These composites showed excellent performance towards the catalytic conversion of biomass-derived levulinic acid (LA) to a biofuel additive ethyl levulinate (EL). The enhancement in the selectivity of EL was observed from 69 to 97% with the incorporation of HT into SBA-15. The experimental results revealed that the catalytic activity of the composites was thoroughly influenced by the density of surface basic sites and surface area. Among all the composites, HTS-2 outperforms the highest EL selectivity of 97.2% with remarkable stability and recyclability.

Anomalous behavior of H2 storage in photocatalytic splitting of water over Fe nanoparticles loaded on Al-modified SBA-15 composites via microwave or ultrasonic treatment routes

Photo-catalytic semiconducting composites were designed and tested in water splitting process for hydrogen generation/storage under visible light irradiation. Iron oxide NPs (5 wt%) were loaded onto Al (25 wt%)-modified SBA-15 supports via microwave-assisted (M) and ultrasonic-assisted (U) routes. Various Al-ِmodification methods of SBA-15 were applied, namely, impregnation post synthesis (Al/S(Imp)), ultrasonic post synthesis (Al/S(Us)) and in situ direct synthesis (Al/S(Inst)). Several techniques were adopted to characterize the as-synthesized composites, viz., XRD, XRF, N2 adsorption-desorption, FTIR, TPR, NH3-TPD, H2 chemisorption, TEM-EDS, DSC-TGA and UV abosorbance. The obtained results showed that all the studied catalysts are rather suitable candidates for H2 storage with maximum capacity, referred probably to the fitting modifications in the pore system and the whole structure of the catalyst samples. The applied loading routes have led to different characteristics of the finished catalytic systems, where the ultrasonic-assisted loading route showed more prevailing behavior in the photo-catalytic splitting process.

Hierarchical structure ZSM-5/SBA-15 composite with improved hydrophobicity for adsorption-desorption behavior of toluene

Hydrophobic zeolites have been considered as one of the most promising adsorbents for capturing volatile organic compounds (VOCs). In this contribution, hierarchically structured ZSM-5/SBA-15 composites with different morphologies including platelet, hexagonal prism, long-hexagonal prism, and long-rod were prepared. All materials were characterized using XRD, SEM, and TEM-EDX, which confirmed that the high dispersion of two zeolites within the composites. Due to the presence of intracrystalline mesopores that could shorten the diffusion pathway of toluene, the composites resulted in increased effective diffusion and higher adsorption capacity. The composites also possess higher hydrophobicity, leading to much better toluene adsorption performance under humid conditions. The water contact angle of ZSM-5 could be increased from 15.6° to 44.9° by forming well dispersed zeolite composites. The 29Si MAS NMR results confirmed that the composites possess higher amount of Q4 groups (75.3%–80.1%), which is the intrinsic reason for higher hydrophobicity. Notably, ZSM-5/SBA-15-hexagonal prism resulted in the best adsorption performance and cycling stability when compared with pure ZSM-5, the breakthrough time was increased from 20.8 to 49.4 min under dry conditions and from 5.9 to 27.3 min in the presence of 50% relative humidity. This work represents an important scheme for making hydrophobic zeolite-based VOCs adsorbents with also improved toluene diffusion properties due to the unique hierarchical porous structure.

Large surface and pore structure of mesoporous WS2 and RGO nanosheets with small amount of Pt as a highly efficient electrocatalyst for hydrogen evolution

In this work, mesoporous WS2 with high surface area was prepared by hard template method. First, a one-step nanocasting generates metal precursor@mesoporous silica SBA-15 composites. A hydrothermal method is subsequently adopted to convert the precursors to sulfides in the confined nanochannels. After etching silica SBA-15, mesoporous layered metal sulfide crystals were obtained as the products. Then, we have put forward a new catalyst based on mesoporous WS2, RGO nanosheets and Pt nanoparticles as a highly efficient electrocatalyst for hydrogen evolution. The Pt/WG-2 nanostructure electrocatalyst in this report exhibits excellent performance with a small Tafel slope of 47 mV dec−1, long-term durability and an overpotential of 95 mV in 0.5 M H2SO4 for the hydrogen evolution reaction (HER).

Ordered micro-mesoporous carbon from palm oil cooking waste via nanocasting in HZSM-5/SBA-15 composite: Preparation and adsorption studies.

This work reports the preparation of HZSM-5/SBA-15 micro-mesoporous materials with composite structure by mechanosynthesis and their use as templates to micro-mesoporous carbons, with palm oil cooking waste as carbon source. HZSM-5/SBA-15 composites were prepared in different mass proportions (25:75, 50:50 and 75:25) by a mechanosynthetic strategy. The palm oil waste was infiltrated into the template pores by a two-step procedure involving grinding followed by stirring the suspension in an oil solution and carbonization under inert atmosphere. SEM images showed the efficiency of mechanosynthesis for all mass proportions, while textural properties were strongly influenced by the presence of SBA-15. A comparison of 50% HZSM-5/SBA-15 mixture with pristine SBA-15 and uncalcined SBA-15 as carbon templates evidenced that the 50% HZSM-5/SBA-15 mixture lead to the carbon with the highest surface area and pore volume. The resulting carbon material was studied as adsorbent to different dye molecules, including molecules with different charges and sizes. Results revealed that the carbon has a significantly higher affinity for cationic dyes, that the mesopore structure favors high diffusion rates and that the surface groups have a very high affinity for cationic dye molecules.

Atomic implantation synthesis of Fe-Cu/SBA-15 nanocomposite as a heterogeneous Fenton-like catalyst for enhanced degradation of DDT

Fe and Cu containing SBA-15 composites (Fe-Cu/SBA-15) were successfully prepared by atomic implantation method. The samples were characterized by XRD, SEM, TEM, FTIR, BET, EDX and XPS. From these results, it reveals the existence of the both (Fe2+ and Cu2+) metals ions in the SBA-15 framework. A series of Fex-Cuy/SBA-15 composites with different Fe content degradation of 4,4-Dichloro-Diphenyl-Trichloroethane (DDT) under the simulated sun-light irradiation using H2O2 as an oxidant agent. This clearly indicated that Cu+ reduce Fe3+ to Fe2+ and consequently, enhancing the catalytic activity. Effects of pH, H2O2 concentration and catalyst dosage were investigated. The best conditions were found to be pH of 5; 3 mM of H2O2 concentration, 0, 4 g L−1 catalyst and reaction time of 4 h at room temperature. The novel Fe-Cu/SBA-15 composite exhibited highly photocatalytic performance of DDT degradation and the conversion reached to the value of 92.3% for the 10Fe-2Cu/SBA-15 composite after 4 h of reaction.

Improving the Catalytic Performance of Keggin [PW12O40]3- for Oxidative Desulfurization: Ionic Liquids versus SBA-15 Composite.

Different methodologies were used to increase the oxidative desulfurization efficiency of the Keggin phosphotungstate [PW12O40]3− (PW12). One possibility was to replace the acid proton by three different ionic liquid cations, forming the novel hybrid polyoxometalates: [BMIM]3PW12 (BMIM as 1-butyl-3-methylimidazolium), [BPy]3PW12 (BPy as 1-butylpyridinium) and [HDPy]3PW12 (HDPy as hexadecylpyridinium. These hybrid Keggin compounds showed high oxidative desulfurization efficiency in the presence of [BMIM]PF6 solvent, achieving complete desulfurization of multicomponent model diesel (2000 ppm of S) after only 1 h, using a low excess of oxidant (H2O2/S = 8) at 70 °C. However, their stability and activity showed some weakness in continuous reused oxidative desulfurization cycles. An improvement of stability in continuous reused cycles was reached by the immobilization of the Keggin polyanion in a strategic positively-charged functionalized-SBA-15 support. The PW12@TM–SBA-15 composite (TM is the trimethylammonium functional group) presented similar oxidative desulfurization efficiency to the homogeneous IL–PW12 compounds, having the advantage of a high recycling capability in continuous cycles, increasing its activity from the first to the consecutive cycles. Therefore, the oxidative desulfurization system catalyzed by the Keggin-type composite has high performance under sustainable operational conditions, avoids waste production during recycling and allows catalyst recovery.

Effect of Filler Treatment on the Release Properties of Coating on Urea Granules

ABSTRACTPolyurethane composite coatings on urea granules were prepared by SBA-15 mesoporous silica (in as-synthesized and calcined forms) as a pseudo-crosslinker without any other chain extenders. The calcination of mesoporous silica leaded to reduction of hydroxyl groups and increase of mesopores. The composite coating containing calcined SBA-15 showed enhanced controlled release properties compared with the other two coatings. At the loading content of 1 wt%, the initial release rate and release duration of urea coated by polyurethane/calcined SBA-15 composite were 0.08% and 83 d, respectively. It is shown that the calcination played an important role in controlling the properties of composite coating.

Enhanced cracking of bulky hydrocarbons over hierarchical ZSM-5 materials: a comparative study

A comparative study of hierarchical ZSM-5 materials including nanosized ZSM-5 (Nano-ZSM-5), nanosized ZSM-5/SBA-15 composite (Com-ZSM-5) and mesoporous ZSM-5 (Meso-ZSM-5) for the enhanced cracking of bulky hydrocarbons is reported. The studied materials were thoroughly characterized by XRD, SEM, TEM, N2-sorption, AAS, ICP-AES, NH3-TPD, FTIR of adsorbed pyridine before being tested in the cracking of 1,3,5 tri-isopropyl-benzene (TIPB) as a representative of bulky hydrocarbons. It was found that all synthesized hierarchical ZSM-5 materials exhibit the preservation of intrinsic, strong Bronsted acidity of ZSM-5 along with the enlarged external/mesoporous surface. The catalytic test results show that these hierarchical ZSM-5 materials indeed promote successive cracking reactions, leading to the enhanced TIPB conversion and selectivity to the deep cracking products, i.e. cumene and benzene compared to those of bulk, commercial ZSM-5. However, the development of mesoporosity by reducing the crystal size of ZSM-5 appears limited (Smeso = 134 m2 g−1). As a result, Nano-ZSM-5 affords only the moderate TIPB conversion and selectivity to deep cracking products (ca. 70% and ca. 20% respectively). Remarkably, the introduction of either intercrystalline mesopores by dispersion of Nano-ZSM-5 in the mesoporous SBA-15 analog matrix (Com-ZSM-5) or intracrystalline mesopores by the alkaline-acid treatments (Meso-ZSM-5) significantly improves the external/mesoporous surface (Smeso = 233–297 m2 g−1), giving rise to both the high TIPB conversion and selectivity to the deep cracking products (ca. 90% and ca. 25% respectively).

Excellent performance of ordered Ag-g-C3N4/SBA-15 for photocatalytic ozonation of oxalic acid under simulated solar light irradiation

Abstract Ordered Ag-g-C 3 N 4 /SBA-15 was successfully synthesized using SBA-15 as a template and support. The samples were characterized by TEM, XRD, XPS, N 2 adsorption-desorption. The results showed that metallic silvers with diameter 15 nm were distributed on the surface of g-C 3 N 4 thin-layered. The specific surface area of the composite was 563.4 m 2 g −1 . As the final products for ozonation, oxalic acid was used to investigate its catalytic ability in heterogeneous photocatalytic ozonation under simulated solar light irradiation. Ordered Ag-g-C 3 N 4 /SBA-15 with the mass ratio of silver nitrate/dicyandiamide around 4% was found to be the most efficient for oxalic acid degradation. The kinetic constant was 1.60 and 2.52 times as high as that of solar light/Ag-g-C 3 N 4 /O 3 and solar light/g-C 3 N 4 /O 3 process, respectively. It demonstrated that both the Ag nanoparticles and improved specific surface area contributed to the enhancement, which promoted the decomposition of O 3 and increased the active sites in reaction. The synergy index for photocatalytic ozonation of oxalic acid was calculated to be 5.71, which indicated a superior synergistic effect between photocatalysis and ozonation. In addition, 4% Ag-g-C 3 N 4 /SBA-15 samples showed good stability in photocatalytic ozonation process by cycled for four times, and the mechanism was also confirmed in this study. It is suggested that Ag-g-C 3 N 4 /SBA-15 composites is a promising catalyst for the practical application of photocatalytic ozonation.

Confinement effect on ultrafast events of a salicylideneaniline derivative within mesoporous materials

We report on femtosecond (fs) studies of HBA-4NP interacting with MCM41, Al-MCM41 and SBA15 materials, and discuss the dynamics of caged monomers and J-aggregates. For MCM41 and Al-MCM41 composites, and upon excitation at 380 nm (monomers region) the ultrafast dynamics (250 fs and 2.5 ps for HBA-4NP/MCM41, 350 fs and 3.5 ps for HBA-4NP/Al-MCM41) is slower than that observed in solution due to aggregates formation inside the material pores. While exciting at 410 nm, we got a slower behaviour. However, for HBA-4NP/SBA15 composites, with a low loading, where the caged monomers are the main guests, we recorded faster dynamics (200 fs and 2 ps) independently on the pumping wavelength. These results show how the properties of mesoporous materials, especially its pore size and Al-doping, affect the nature of the formed composites and their ultrafast photodynamics.

ZSM-5/SBA-15 versus Al-SBA-15 as supports for the hydrocracking/hydroisomerization of alkanes

Al-SBA-15 and ZSM-5/SBA-15 (ZSC) composite were synthesized following hydrothermal procedures in the presence of triblock copolymer Poly(ethylene glycol)- poly(propylene glycol)-poly(ethylene glycol) (Pluronic P123) and a mixture of tetrapropylammonium bromide (TPABr)/Pluronic P123 templates, respectively. Pt(0.5wt.%)/Al-SBA-15 and ZSC bifunctional catalysts were then prepared by a wet impregnation methodology and investigated in the hydrocracking/hydroisomerization of n-decane. Pt/ZSC, containing a trimodal porous texture and high Brønsted acidity, exhibited hydrocracking activity while Pt/Al-SBA-15, showing merely Lewis acidity, was active for hydroisomerization. At 300°C the conversion of n-decane on Pt/ZSC reached 98% and cracking selectivity was about 99%. Both catalysts were exhaustively characterized.

Visible light photocatalytic degradation of herbicide (Atrazine) using surface plasmon resonance induced in mesoporous Ag-WO3/SBA-15 composite

Atrazine is one of the most extensively used herbicides. Being non-biodegradable in nature, it has a long half-life in water and hence it is prone to contaminate the water bodies and even seeps into the ground to pollute underground water. In this study, we developed a photocatalytic method for the degradation of Atrazine in water samples. Highly ordered mesoporous Ag-WO3/SBA-15 composites were tested as photocatalysts for the degradation of atrazine in water. It was found that 40% WO3 loading rendered an optimum surface area and material content in the SBA-15 template and hence favored the enhanced photocatalytic degradation of atrazine in water. The further addition of Ag onto the WO3/SBA-15 composite not only made this catalyst very effective in the most sought visible region due to solar energy harvesting, but also significantly reduced the electron hole recombination as evidenced by photoluminescence studies to enhance the degradation efficiency. As a result, the Ag-WO3/SBA-15 composite the photo-catalytic degradation of atrazine in water under visible radiation was significantly enhanced.