Large External Surface Area Research Articles

Layered silicate PLS-3 with PREFER structure supported Pd nanoparticles: A recyclable catalyst for the synthesis of furfuryl ethyl ether

Supported Pd catalysts has found wide applications in reductive etherification of aldehydes. However, the synthesis of furfural-derived ethers on Pd catalysts has encountered great challenges because several side reactions such as over-hydrogenation of furan ring and decarbonylation always occur simultaneously under the reaction conditions. We herein reported the catalytic performance of Pd nanoparticles (∼4 nm) supported on the external surface of layered structured PLS-3 zeolite with narrow pore size (<0.4 nm) and large external surface area (80–100 m2/g). The PLS-3 with Si/Al of 92 having total acid sites of 93 μmol/g showed satisfied ether selectivity. Pd nanoparticles located on the external surface showed better etherification selectivity than those confined in the framework, due to the less diffusion limitation of furfural acetal as an intermediate.

CaO catalysts supported on ZSM-5 zeolite for biodiesel production via transesterification of rapeseed oil

This paper deals with the effect of Si/Al ratio and form of zeolite support on the catalytic properties of the CaO catalysts in transesterification reaction of rapeseed oil with methanol. The reaction was conducted at 180 and 220 °C. To get the intended purposes of the work a various calcium oxide (CaO) catalysts supported on the ammonium and hydrogen forms of ZSM-5 zeolites with different Si/Al ratios were prepared by impregnation method. The results showed that the most active zeolite-based catalyst was 10%CaO/ZSM-5 (Si/Al = 50) system in the transesterification reaction at both temperatures 180 and 220 °C, which exhibited triglycerides (TG) conversion equal to 72.7 and 95.2% and fatty acid methyl esters (FAME) yield of 56.9 and 91.1%, respectively. High reactivity of this catalyst is explained by its acid-base properties, crystallite size of active phase, large external surface area and uniform distribution of the CaO on catalyst surface compared to the other investigated CaO systems supported on ZSM-5 zeolites. In addition, the analysis of the product obtained in the transesterification process carried out on the 10% CaO/ZSM-5 (Si/Al = 280) catalyst at 220 °C confirmed the presence of the following methyl esters of higher fatty acids: methyl oleate, methyl linoleate, methyl linolenate, methyl stearate, methyl eicosenoate, methyl palmitate, methyl palmitoleate, methyl nervonate and methyl arachidate.

Catalytic pyrolysis of lignin to aromatic hydrocarbons over Nb/Al oxide catalyst

Catalytic fast pyrolysis (CFP) of lignin aiming monocyclic aromatic hydrocarbons (MAHs) is attractive. Five metal oxide catalysts (named c-Nb3Alx) with different Nb/Al ratios, c-Nb, c-Al, c-Nb3Al1, c-Nb3Al2 and c-Nb3Al3 were synthesized and applied to CFP of lignin. Among these catalysts, c-Nb3Al2 exhibits excellent deoxygenation ability and the highest selectivity for MAHs (77.0 %). The selectivity and deoxygenation capacity of c-Nb3Al2 for MAHs were higher than H-ZSM-5 (25) as a control. It was attributed to the large external surface area (90 m2g-1), mesoporous structure (16.15 nm) and high acid amount (2.00 mmolNH3/gcat) of c-Nb3Al2. The c-Nb3Al2 has good stability and can be regenerated by simple calcination. The selectivity of the regenerated c-Nb3Al2 for MAHs was still high at 70.1 %. Guaiacol was used to compare the difference in the deoxygenation capacity of c-Nb3Al2 and H-ZSM-5.

ПРИМЕНЯЕМОСТЬ ВОДОГАЗОВЫХ ФОРСУНОК ДЛЯ ПОЖАРОТУШЕНИЯ ТОНКОРАСПЫЛЕННОЙ ВОДОЙ

The low efficiency of traditional water extinguishing systems is due to the formation of large droplets. Large droplets have a small external surface area, which causes poor heat removal from the ignition source. A large external surface area of droplets is provided by fire extinguishing systems with thinly sprayed water. They are effective in extinguishing fires at the initial stage of a fire in confined spaces and ensure the formation of droplets less than 150 microns. The analysis showed that water-gas nozzles with co-directional flows of water and gas are suitable for creating finely dispersed water with a droplet size of less than 100 microns. To ensure significant heat removal from the ignition source, the average diameter of the droplets of finely dispersed water should be less than 80 microns. A technique for determining the size of droplets when sprayed with water-gas nozzles is presented. According to the method, the calculation of the average diameter of droplets was carried out depending on the ratio of volume flow rates of gas and water. It is shown that fire extinguishing with finely sprayed water with the help of water-gas nozzles is effective at a gas pressure in front of the annular gap from 0,4 MPa to 0,6 MPa and the ratio of volumetric air flow to volumetric water flow is more than 2 000.

Encapsulating platinum nanoparticles into multi-hollow silicalite-1 zeolite for catalytic oxidation of volatile organic compounds

Platinum nanoparticles (Pt NPs) embedded in the multi-hollow silicalite-1 zeolite (Pt@MH-S-1) were prepared by the sequential alkali etching and recrystallization of parent microporous silicalite-1 zeolite. Then, toluene and acetone were employed as probe molecules to determine the catalytic behavior of Pt@MH-S-1 for the elimination of volatile organic compounds (VOCs). The results reveal that Pt@MH-S-1 with multi-hollow structure owns large external specific surface area for dispersing the Pt NPs, and abundant mesoporous channels for improving the accessibility of toluene to Pt NPs as well as high reactive oxygen content, excellent toluene adsorption capacity and moderate adsorption strength. Owing to these characteristics, Pt@MH-S-1 exhibits superior performance both in toluene and acetone catalytic oxidations as reflected by 100% conversion acquired at even a low temperature of 137 and 180 °C, respectively. Moreover, Pt@MH-S-1 also shows good stability toward the various conditions, signifying its superiority and potential in practical application for VOCs treatment.

An extensive exploration of non-conventional sources for preparing NiS and its potential applications in battery and photodegradation processes

In this study, we explore the synthesis of transition metal sulphide nanoparticles, focusing on the effects of different fabrication methods on their morphology and performance. We compare the single source method (S-M) and multisource method (M-M) precursors to understand their contrasting properties. Through comprehensive characterization using PXRD, EDX, SEM, TEM, HRTEM, and XPS, we analyze the resulting nanomaterials. Electrochemical performance is evaluated for NiS nanoparticles produced via the S-M method, specifically in the context of Li/Li+ batteries. Additionally, we assess the photocatalytic activity of both materials across the entire spectrum for dyes such as methyl violet, malachite green, methylene blue, and rhodamine B. Our findings indicate that the S-M method yields nanomaterials with a larger external surface area, leading to superior photocatalytic activity compared to the M-M method. These results highlight the substantial influence of the fabrication method on the final morphology and performance of the synthesized nanomaterials.

Production of high-carbon-number bio-aviation fuels from furans using sulfated zirconia and silica-alumina aerogel catalysts

Lignocellulose can help produce fuels in biorefineries through its fractionated components such as cellulose, hemicelluloses, and lignin. For instance, hemicellulose-derived xylose has been studied for obtaining petroleum-substituting fuels. Therefore, in this study, catalytic hydroalkylation/alkylation (HAA) of xylose-derived 2-methylfuran (2-MF) with butanal was targeted to selectively produce high-carbon-number diesel fuels. To that end, silica–alumina (SiAl) aerogels with different Si/Al ratios and a series of sulfated zirconia (SZ) compounds calcined at various temperatures were prepared as catalysts to overcome the limitations of conventional hazardous homogeneous acid catalysts. The activity of the SiAl catalysts in forming the desired HAA product, 5,5-bissylvylbutane (denoted as BB), was found to be directly related to the number of acid sites and acid density. Moreover, increasing the Si/Al molar ratio, which reduced the acid density and number of acid sites, led to lower 2-MF conversions and BB yields. The optimal 2-MF conversion and BB yield with the SiAl catalysts (67 % and 45 %, respectively) were achieved using a Si/Al ratio of 8:2 mol/mol. Furthermore, SZ calcined at 700 °C (denoted as SZ-700) exhibited the highest activity among the SZ catalysts (72 % 2-MF conversion, 63 % BB yield), despite having the fewest acid sites and lowest acid density. This was presumably because of the physical structure of SZ-700, which featured mixed monoclinic and tetragonal phases, many oxygen vacancies, and a large accessible external surface area, which facilitated the HAA reactions. Hydrogenation and hydrodeoxygenation (HDO) of BB were performed thereafter using Pd/C and Ru/SiO2–Al2O3 catalysts, respectively. The resulting deoxygenated hydrocarbons comprised 15.1 % light hydrocarbons (C4–C8) and 83.1 % heavier hydrocarbons (C9–C20). Simulated distillation analysis of the post-HDO product distribution indicated that the liquid-phase product contained 70 % high-carbon-number bio-aviation fuels.

Catalytic conversion of lignin into monoaromatic hydrocarbons over a Ni/Al hydrotalcite-derived catalyst

Lignin is the most abundant aromatic biopolymer. Thus, preparation of BTX (benzene, toluene and xylenes) by catalytic fast pyrolysis (CFP) of lignin is attractive. Ni-Al mixed metal oxide (MMO) catalysts, derived from pyrolyzing Ni-Al layered double hydroxides (LDH), were prepared for the catalytic fast pyrolysis of lignin. The effects of catalyst Ni/Al ratio, catalyst dosage and pyrolysis temperature on the liquid products were investigated by Py-GC/MS. The Ni3Al3-MMO produced the best liquid product distribution from lignin at 700 ℃. The selectivity of Ni3Al3-MMO for aliphatic hydrocarbons and monocyclic aromatic hydrocarbons (MAHs) was 18.0% and 78.2%, respectively. The selectivity to polyaromatic hydrocarbons (PAHs) was 3.8%. No phenols and phenolic derivatives were produced. This is related to the mesoporous catalytic structure (pore size of 14.37 nm), large external surface area (134.74 m2/g) and strong acidity (4.92 mmolNH3/g) of Ni3Al3-MMO. In addition, a mechanistic study was performed with the lignin model compound (guaiacol) showing that Ni3Al3-MMO exhibits strong deoxygenation activity for aromatic C–O bond cleavage of lignin.

Fe-MFI zeolite-encapsulated copper oxide with excellent re-usability for efficient tetracycline degradation

Impregnation handlement can load highly dispersed CuO nanoparticles on the Fe-MFI zeolite and effectively enhances its catalytic activity in the tetracycline degradation reactions, but encounters serious re-usability problems. In this work, Fe-MFI zeolite-encapsulated copper oxide CuO@Fe-MFI was prepared via one-step hydrothermal synthesis and utilized as heterogeneous catalyst for the removal of tetracycline. The obtained 2CuO@1Fe-MFI zeolite presented a external surface area of 270 m2/g, which was almost 5.5 folds of 2CuO/1Fe-MFI zeolite obtained by impregnation handlement. In addition, there may be a near-neighbor effect between encapsulated CuO and framework iron evidenced by the shifts of UV–Vis absorption bands as well as binding energies for Fe 2p and Cu 2p. At pH = 7.0, 2CuO@1Fe-MFI zeolite attained the largest tetracycline removal rate of 99.6% within 20 min at experimental conditions: [TCE] = 50 mg/L, [Catalyst] = 0.5 g/L, [PMS] = 1.0 g/L, 323 K, and the biggest degradation rate constant of 2.42 min−1, which was almost 11.1 folds of that for 2CuO/1Fe-MFI zeolite. The large external surface area and near-neighbor effect together gave rise to the excellent tetracycline degradation performance for 2CuO@1Fe-MFI zeolite. On the same time, the obtained 2CuO@1Fe-MFI zeolite can be reused for more than five times. Quenching experiments and EPR characterizations demonstrated the reactive species for tetracycline removal over 2CuO@1Fe-MFI zeolite were •OH, SO4•−, •O2− and 1O2 species, and moreover 1O2 served as the major active species. Furthermore, possible tetracycline degradation pathways over 2CuO@1Fe-MFI zeolite were proposed.

Influence of Additives and Growth Inhibitors in Improving the Physicochemical Properties of Silicoaluminophosphate Molecular Sieve, SAPO-11.

Silicoalumiophosphates (SAPOs) are microporous crystalline materials extensively utilized as adsorbents and catalysts. The present work utilized two strategies to synthesize nanocrystalline SAPO-11. The first strategy involves a surfactant as a mesoporogen to reduce the crystallite size and increase the surface area for the materials synthesized at 200 °C in 2 days. In the second strategy, the synthesis temperature and time were significantly reduced to 160 °C and 3 h using propylene oxide as a pH accelerator. The reduction in the particle size and the improvement in the surface area were achieved using propyltriethoxysilane, which inhibited the growth of SAPO-11 particles. The materials were thoroughly characterized using XRD, N2-sorption, FTIR, pyridine-adsorbed FTIR, electron microscopy, XPS, and NMR. The surfactant-assisted synthesis formed a nanorod morphology with a large external and BET surface area. The low-temperature synthesis involving silane as a growth inhibitor demonstrated a rectangular nanoplatelet morphology with a large surface area. The synthesis was scaled up to 10 g with no change in the experimental parameters. A synthesis strategy facilitating nuclei formation and retarding the growth of particle size will attract academia and industrial researchers to utilize these strategies for the manufacturing of zeolites of different frameworks on a large scale.

Front Cover: Fine‐Tuning Texture of Highly Acidic HZSM‐5 Zeolite for Efficient Ethanol Dehydration (ChemCatChem 9/2023)

The Front Cover illustrates how different morphologies of highly acidic ZSM-5 zeolite control the product distribution of ethanol dehydration. In their Research Article, E. J. M. Hensen, C. Wattanakit and co-workers demonstrate that very thin nanolayers of this zeolite with a large external surface area and abundant mesopores enhance the ethylene yield up to 95% with a high longevity. In contrast, nanoplate and bulk structures of ZSM-5 result in low ethanol conversion, high selectivity to diethyl ether, and rapid deactivation. Reducing the crystal size of highly acidic zeolites to ultra-thin nanosheets can shorten the residence time of ethanol and its intermediates in the shape-selective environments, significantly suppressing the formation of coke precursors and achieving high and stable yield of the important chemical building block ethylene. More information can be found in the Research Article by E. J. M. Hensen, C. Wattanakit and co-workers.

Ring-opening of furfuryl alcohol to pentanediol with hierarchically structured Cu-MFI catalysts

Metal-acid bifunctional catalysts often encounter deactivation troubles due to carbon deposition and metal agglomeration. Herein, a hierarchically porous structured Cu-MFI-AEH catalyst was developed for selective ring-opening of furfuryl alcohol to pentanediols, which exhibits >90% yield of pentanediols and improved stability. The synergistic effect of nano-copper species and Brønsted acidic protons boosts the ring opening of furfuryl alcohol. This was also disclosed by the DFT technique that small-size Cu possesses better hydrogen dissociation performance, and the introduction of ≡Si (OH) Al≡ (Brønsted acidic protons) promotes the adsorption of furfuryl alcohol and reduces the ring opening energy barrier of furfuryl alcohol. The obtained highly porous catalyst possesses a large external surface area and large pore volume, which are beneficial to offer accessible active sites and accelerate product transport, eventually resulting in superior anti-coking performance. Furthermore, the abundant silanol groups on the MFI surface produced by ammonia treatment could act as an anchoring site for grafting Cu species, resulting in strong metal-support interaction and highly anti-sintering performance. The results reported herein provide a novel strategy to improve the stability and activity of copper-based catalysts. It also inspires the conversion of biomass resources into high value-added oxygenated fine chemicals.

Carbon Nano-Onion-Encapsulated Ni Nanoparticles for High-Performance Lithium-Ion Capacitors

Lithium-ion capacitors (LICs) feature a high-power density, long-term cycling stability, and good energy storage performance, and so, LICs will be widely applied in new energy, new infrastructure, intelligent manufacturing. and other fields. To further enhance the comprehensive performance of LICs, the exploration of new material systems has become a focus of research. Carbon nano-onions (CNOs) are promising candidates in the field of energy storage due to the properties of their outstanding electrical conductivity, large external surface area, and nanoscopic dimensions. Herein, the structure, composition, and electrochemical properties of carbon nano-onion-encapsulated Ni nanoparticles (Ni@CNOs) have been characterized first in the present study. The initial discharge and charge capacities of Ni@CNOs as anodes (in half-cells (vs. Li)) were 869 and 481 mAh g−1 at 0.1 A g−1, respectively. Even at a current density of 10 A g−1, the reversible specific capacity remained at 111 mAh g−1. Ni@CNOs were used as anode materials to assemble LICs (full pouch cells (vs. activated carbon)), which exhibited compelling electrochemical performance and cycle stability after optimizing the mass ratio of the positive and negative electrodes. The energy density of the LICs reached 140.1 Wh kg−1 at 280.2 W kg−1 and even maintained 76.6 Wh kg−1 at 27.36 kW kg−1. The LICs also demonstrated excellent cycling stability with a 94.09% capacitance retention over 40,000 cycles. Thus, this work provides an effective solution for the ultra-rapid fabrication of Ni-cored carbon nano-onion materials to achieve high-performance LICs.

Enhanced CO2 separation performance by incorporating KAUST-8 nanosheets into crosslinked poly(ethylene oxide) membrane

The trade-off relationship between permeability and selectivity as well as plasticization issues have largely impeded the advancement of membrane technology. Mixed-matrix-membranes (MMMs) with the incorporation of fillers into the polymer matrix is one promising method to deal with these challenges by carefully tuning their chemical properties. Compared with nanoparticles, the counterpart of nanosheet has a larger external surface area with a tendency to have closer contact with a polymer matrix to form a defect-free membrane at higher loading. This work successfully synthesized a high aspect ratio (30/1) of KAUST-8 nanosheets with high CO2 uptake (60 cm3/g). This enables an optimal loading of 30 wt.% in the CO2-attractive crosslinked poly(ethylene oxide) (XLPEO) membrane and results in the simultaneously enhanced CO2 permeability and CO2/N2 selectivity with 280 % and 30 % up, respectively in the mixed gas permeation measurements (50/50 vol.). The resultant membrane performance surpassed the 2008 Robeson upper bound. Meanwhile, the stabilized MMM performance of up to 6 bar and high thermal stability of up to 350 °C bring extra benefits to the KAUST-8-based XLPEO membrane for post-combustion flue gas treatment.

Amorphous Aluminosilicate Nanosheets as Universal Precursors for the Synthesis of Diverse Zeolite Nanosheets for Polymer-Cracking Reactions.

Zeolites catalyze some reactions in their molecular-sized pores, but large molecules can react only on their external surface. Zeolite-nanosheets (NSs) have been developed as catalysts for large molecules. The previously reported methods to synthesize zeolite-NSs are specialized for each zeolite type. Here we propose a new method to synthesize various zeolite-NSs from the same amorphous aluminosilicate NSs (AAS-NSs) as a universal precursor. We successfully synthesized the unprecedented AAS-NSs in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase. The four zeolite types could be obtained from the single-species AAS-NSs. These results imply that this method enables us to synthesize almost all types of zeolite-NSs. Moreover, the synthesized CHA-NSs have great potential for various applications because of their thickness and large external surface area.

Amorphous Aluminosilicate Nanosheets as Universal Precursors for the Synthesis of Diverse Zeolite Nanosheets for Polymer‐Cracking Reactions

AbstractZeolites catalyze some reactions in their molecular‐sized pores, but large molecules can react only on their external surface. Zeolite‐nanosheets (NSs) have been developed as catalysts for large molecules. The previously reported methods to synthesize zeolite‐NSs are specialized for each zeolite type. Here we propose a new method to synthesize various zeolite‐NSs from the same amorphous aluminosilicate NSs (AAS‐NSs) as a universal precursor. We successfully synthesized the unprecedented AAS‐NSs in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase. The four zeolite types could be obtained from the single‐species AAS‐NSs. These results imply that this method enables us to synthesize almost all types of zeolite‐NSs. Moreover, the synthesized CHA‐NSs have great potential for various applications because of their thickness and large external surface area.

Recent Developments in Activated Carbon Catalysts Based on Pore Size Regulation in the Application of Catalytic Ozonation

Due to its highly developed pore structure and large specific surface area, activated carbon is often used as a catalyst or catalyst carrier in catalytic ozonation. Although the pore structure of activated carbon plays a significant role in the treatment of wastewater and the mass transfer of ozone molecules, the effect is complicated and unclear. Because different application scenarios require catalysts with different pore structures, catalysts with appropriate pore structure characteristics should be developed. In this review, we systematically summarized the current adjustment methods for the pore structure of activated carbon, including raw material, carbonization, activation, modification, and loading. Then, based on the brief introduction of the application of activated carbon in catalytic ozonation, the effects of pore structure on catalytic ozonation and mass transfer are reviewed. Furthermore, we proposed that the effect of pore structure is mainly to provide catalytic active sites, promote free radical generation, and reduce mass transfer resistance. Therefore, large external surface area and reasonable pore size distribution are conducive to catalytic ozonation and mass transfer.

Ni-Loaded 2D Zeolitic Imidazolate Framework as a Heterogeneous Catalyst with Highly Activity for Ethylene Dimerization

Metal–organic frameworks (MOFs) hold great potential in heterogeneous catalysis due to their unique properties and tunable structures. Zeolitic imidazolate frameworks (ZIFs) are series of classical MOFs that have been widely studied, where Zn2+ is coordinated with four imidazoles to form a tetrahedral structure. ZIF-L, one type of ZIF, is known for its unique two-dimensional (2D) leaf-like morphology and large external specific surface area. In this work, we reported a facile and green synthesis of the Ni-loaded ZIF-L (Ni-ZIF-L) catalysts, where water as solvent and product collection by filtration make the preparation easy for large-scale industrial production. Considering the incompatibility of the d8 electron configuration of Ni with the three-dimensional (3D) framework of ZIF-L, Ni can only be selectively anchored to the surface of ZIF-L. The Ni-ZIF-L has shown high crystallinity and 2D leaf-like microflakes similar to those of pure ZIF-L. After systematic analysis, we speculate that the Ni sites in Ni-ZIF-L samples have a square planar configuration, which should be coordinated by two imidazole groups from the framework, one NO3– group, and one free imidazole group. Ni-ZIF-L possesses fully exposed Ni active sites and a large specific surface area, accounting for the good performance for ethylene dimerization. In addition, the large particle size of the Ni-ZIF-L catalyst is beneficial for separation. With the assistance of cocatalyst, Ni-ZIF-L achieves an average ethylene turnover frequency of 330 320 moles of ethylene per mole of Ni per hour (1-butene selectivity >90%)) under 40 °C and 30 bar, comparable to the activity of the benchmark heterogeneous catalyst. The isotope experiments are used to illustrate that the ethylene dimerization catalyzed by Ni-ZIF-L follows the Cossee-Arlman mechanism, which also rationalizes the high catalytic activity and the small amount of isomerization and trimerization product formation.

ZSM-5 nanocrystal promoted low-temperature activity of supported manganese oxides for catalytic oxidation of toluene

• Nano-sized ZSM-5 zeolite was prepared by amino acid assisted method. • Effect of the support size on the formation of MnO x species was studied. • Small-sized ZSM-5 can highly disperse active MnO x species. • Abundant oxygen vacancies are formed on the MnO x supported by small-sized ZSM-5. • MnO x /Z5-L 0.2 shows excellent low-temperature activity in toluene combustion reaction. Nanoscale zeolites are of great practical interest due to their advantages of favorable mass transfer, accessibility to active sites, and large external surface area. Herein, ZSM-5 ( MFI -type) nano-sized zeolites were prepared by conventional hydrothermal and amino acid-assisted approaches to support MnO x species. The morphology, acidity, textural properties, and chemical state of the prepared MnO x /ZSM-5 samples are comprehensively characterized. The size effect of ZSM-5 nanocrystals on the physicochemical properties of supported MnO x species and on their catalytic oxidation behavior for the combustion of toluene is investigated. Beneficially from the larger surface area and smaller crystal size, the smaller-sized ZSM-5 zeolite (Z5-L 0.2 , ∼100 nm) prepared by the amino acid-assisted method can highly disperse more active MnO x species than the larger ZSM-5 counterpart (∼500 nm). Owing to abundant surface oxygen vacancies and surface adsorbed oxygen, as well as superior low-temperature reducibility, the MnO x supported on nanosized Z5-L 0.2 zeolites exhibits remarkably enhanced low-temperature activity for the catalytic oxidation of toluene.

Charge transformation of framework titanium (Ⅳ) into titanium (Ⅲ) in vanadium-titanium doped MFI zeolite for enhanced alkene epoxidation

Simultaneous insertion of double heteroatom in the MFI framework generally gives rise to synergistic catalysis effect, however the specific origins for synergistic catalysis is still nebulous. In this study, vanadium-titanium doped MFI zeolite was synthesized via one-pot hydrothermal synthesis with the addition of (NH4)2CO3 and applied as heterogeneous catalyst for the synergistic catalysis of 1-hexene and cyclohexene epoxidation. Simultaneous incorporation of vanadium and titanium induced the partial charge transformation of titanium (Ⅳ) into titanium (Ⅲ), which was verified by EPR and XPS characterizations. UV-Raman and UV–Vis spectra disclosed that partial charge transformation mainly occurred for framework titanium (Ⅳ). In addition, simultaneous insertion of vanadium and titanium gave rise to more Lewis acid sites as well as larger external surface area for VTS(0.15) zeolite in comparison to VS(0.15) and TS(0.15) zeolite. The prepared VTS(0.15) zeolite presented a TOF value of 118.8 h−1 for 1-hexene epoxidation, which is 7.8 folds and 1.3 folds of VS(0.15) and TS(0.15) respectively. Partial charge transformation of framework titanium (Ⅳ) into titanium (Ⅲ), robust Lewis acid sites as large external surface area may induce the synergistic catalysis effect for VTS(0.15) zeolite in the epoxidation reactions. Moreover, the obtained VTS(0.15) zeolite particles showed good reusability for more than five cycles.