Terms Of Turnover Frequency Research Articles

Efficiency Conceptualization Model: A Theoretical Method for Predicting the Turnover of Catalysts.

In recent times, the theoretical prediction of catalytic efficiency is of utmost urgency. With the advent of density functional theory (DFT), reliable computations can delineate a quantitative aspect of the study. To this state-of-the-art approach, valuable incorporation would be a tool that can acknowledge the efficiency of a catalyst. In the current work, we developed the efficiency conceptualization model (ECM) that utilizes the quantum mechanical tool to achieve efficiency in terms of turnover frequency (TOF). Twenty-six experimentally designed transition metal (TM) water oxidation catalysts were chosen under similar experimental conditions of temperature, pressure, and pH to execute the same. The computations conclude that the Fe-based [Fe(OTf)2(Me2Pytacn)] (MWOC-17) is a highly active catalyst and, therefore, can endure for more time in the catalytic cycle. Our results conclude that the Ir-based catalysts [Cp*Ir(κ2-N,O)X] with MWOC-23: X=Cl; and MWOC-24: X=NO3 report the highest computed turnover numbers (TONs), of 406 and 490 against the highest experimental TONs, of 1200 and 2000 respectively, whereas the Co-based [Co(12-TMC)]2+ (MWOC-19) has the lowest TONs ( =19, τexperimental TON=16) among the chosen catalysts and thereby successful in corroborating the previous experimental results.

Fluorination of porphyrin β-periphery boosts nickel(II)-catalyzed hydrogen evolution reaction

Tunichlorin, the naturally occurring chlorophyll cofactor containing Ni(II) ion, sets up a golden standard for designing the electrocatalysts for hydrogen evolution reaction (HER) via β-peripheral modification. Besides the fine-tuning of the porphyrin β-periphery such as adjusting the aromatics (the saturated level of tetrapyrrole) or installing hydroxyl group (hydrogen bond network) to enhance the catalytic HER efficiency, here we report that β-fluorination of porphyrin is also an important approach to increase the reactivity of Ni(II) center. Benefiting the previously reported derivatization of β-fluorinated porpholactones, we constructed a β-fluorinated tunichlorin mimic (6). Compared with the non-fluorinated analogs (1, 3, and 5), we found that 2, 4, and 6 exhibit significant electrocatalytic HER reactivity acceleration (in terms of turnover frequencies, TOF, s−1) of ca. 37, 170, 133-fold, respectively. Mechanism studies suggested that β-fluorination negatively shifts the metal complexes' reduction potentials and accelerates the electron transfer process, both contributing to the boosting of HER reaction. Notably, 6 showed an 890-fold increase of TOFs than 1, demonstrating the combining advantages of the of fluorination, hydrogenation, and hydroxylation at porphyrin β-periphery.

Enhanced activity of bimetallic Fe-Cu catalysts supported on ceria toward water gas shift reaction: synergistic effect

Within the “hydrogen chain”, the hight-emperature water gas shift reaction represents a key step to improve the H2 yield and adjust the H2/COx ratio to fit the constraints of downstream processes. Despite the commercial application of the high-temperature water gas shift, novel catalysts characterized by higher intrinsic activity (especially at low temperatures), good thermal stability, and no chromium content are needed. In this work, we propose bimetallic iron-copper catalysts supported on ceria, characterized by low active phase content (iron oxide + copper oxide < 5 wt %). Fresh and used samples were characterized by inductively coupled plasma mass spectrometry, X-ray diffraction, nitrogen physisorption, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, and temperature programmed reduction in hydrogen to relate physicochemical features and catalytic activity. The sample with iron/copper ≈ 1 and 4 wt % active phase content showed the best catalytic properties in terms of turnover frequency, no methane formation, and stability. Its unique properties were due to both strong iron-copper interaction and strong metal-support interaction, leading to outstanding redox behavior.

Kinetic investigation of the promoting effect of cobalt on Pd-Pt/SnO2 catalyzed wet methane combustion

This study is focused on developing a stable and active catalyst for lean-burn methane combustion in the presence of water. By varying the cobalt loading, it was found that 10 wt% Co deposition enhanced the hydrothermal stability of the 1 wt% Pd-Pt (1:1 molar ratio)/SnO2 catalyst. Kinetic investigation of methane combustion on the hydrothermally aged Pd-Pt/10Co/SnO2 catalyst under 5 and 10 vol% water was performed. While SnO2 dictated the kinetics in terms of activation energy (89 ± 9 kJ mol−1), Co addition altered the reaction order to water (n = −0.37). In terms of turnover frequency, the Pd-Pt/10Co/SnO2 catalyst surpassed the Al2O3-supported catalyst formulations. Reaction rates normalized per total catalyst mass at 773 K and 10 vol% added water were found in the order of Pd/Al2O3(“x”) < Pd-Pt/Al2O3 (1.5x) < Pd-Pt/SnO2 (1.6x) < Pd-Pt/10Co/SnO2 (14x), consequently suggesting that the utilization of the Pd-Pt/10Co/SnO2 catalyst could result in small catalytic converter volumes.

A novel cobalt(ii) acetate complex bearing lutidine ligand: a promising electrocatalyst for oxygen evolution reaction.

Developing cost-effective electrocatalysts using earth-abundant metal as an alternative to expensive precious metal catalyst remains a key challenge for researchers. Several strategies are being researched/tested for making low-cost transition metal complexes with controlled electron-density and coordination flexibility around the metal center to enhance their catalytic activity. Herein, we report a novel lutidine coordinated cobalt(ii) acetate complex [(3,5-lutidine)2Co(OAc)2(H2O)2] (1) as a promising electrocatalyst for oxygen evolution reaction (OER). Complex 1 was characterized by FT-IR, elemental analysis, and single crystal X-ray diffraction data. The structure optimization of complex 1 was also done using DFT calculation and the obtained geometrical parameters were found to be in good agreement with the parameters obtained from the solid state structure obtained through single crystal X-ray diffraction data. Further, the molecular electrostatic potential (MEP) maps analysis of complex 1 observed electron rich centers that were found to be in agreement with the solid-state structure. It was understood that the coordination of lutidine as a Lewis base and acetate moiety as a flexible ligand will provide more coordination flexibility around the metal center to facilitate the catalytic reaction. Further, the electron rich centers around metal center will also support the enhancement of their catalytic activity. Complex 1 shows impressive OER activity, even better than the state-of-the-art IrO2 catalyst, in terms of turnover frequency (TOF: 0.05) and onset potential (1.50 V vs. RHE). The TOF for complex 1 is two and half times higher, while the onset potential is ca. 20 mV lower, than the benchmark IrO2 catalyst studied under identical conditions.

Quality or Quantity? How Structural Parameters Affect Catalytic Activity of Iron Oxides for CO Oxidation

The replacement of noble metal catalysts by abundant iron as an active compound in CO oxidation is of ecologic and economic interest. However, improvement of their catalytic performance to the same level as state-of-the-art noble metal catalysts requires an in depth understanding of their working principle on an atomic level. As a contribution to this aim, a series of iron oxide catalysts with varying Fe loadings from 1 to 20 wt% immobilized on a γ-Al2O3 support is presented here, and a multidimensional structure–activity correlation is established. The CO oxidation activity is correlated to structural details obtained by various spectroscopic, diffraction, and microscopic methods, such as PXRD, PDF analysis, DRUVS, Mössbauer spectroscopy, STEM-EDX, and XAS. Low Fe loadings lead to less agglomerated but high percentual amounts of isolated, tetrahedrally coordinated iron oxide species, while the absolute amount of isolated species reaches its maximum at high Fe loadings. Consequently, the highest CO oxidation activity in terms of turnover frequencies can be correlated to small, finely dispersed iron oxide species with a large amount of tetrahedrally oxygen coordinated iron sites, while the overall amount of isolated iron oxide species correlates with a lower light-off temperature.

Dehydro-aromatization of renewable bio-naphtha over Pd/[formula omitted]-Al2O3 catalyst

An effort has been made to eliminate the problem of chlorine loss and equipment corrosion caused by the conventional chlorinated alumina-based reforming noble metal catalyst. The manuscript has reported the gas phase aromatization of renewable bio-naphtha in the molecular hydrogen and monometallic Pd/γ-Al2O3 catalyst. In addition, First-principle density functional theory calculations were considered to calculate the free energy and heat of reaction for the conversion of renewable bio-naphtha into toluene on the surface of Pd/γ-Al2O3. The catalyst was characterized by XRD, SEM, TEM, BET, NH3-TPD, TGA/DTA, XPS, and FTIR. All the experiments were carried out in a stirred batch reactor at various reaction conditions for the dehydroaromatization of bio-naphtha. The maximum selectivity towards aromatics of 72.3% was achieved at the optimal reaction conditions of temperature = 375 °C, PH2 = 5 bar, catalyst mass = 0.6, and the reaction time = 14 h. The reaction and coking kinetics were applied to calculate the activation energy of 78.02 kJ/mol and 16.17 kJ/mol, respectively. The catalyst activity was reported in terms of turnover frequency (TOF), i.e., 90.2 h−1. A plausible mechanism for bio-naphtha aromatization via catalytic dehydrogenation route with the active species Pd (0)/Pd (II) is also elucidated.

Iron atom–cluster interactions increase activity and improve durability in Fe–N–C fuel cells

Simultaneously increasing the activity and stability of the single-atom active sites of M–N–C catalysts is critical but remains a great challenge. Here, we report an Fe–N–C catalyst with nitrogen-coordinated iron clusters and closely surrounding Fe–N4 active sites for oxygen reduction reaction in acidic fuel cells. A strong electronic interaction is built between iron clusters and satellite Fe–N4 due to unblocked electron transfer pathways and very short interacting distances. The iron clusters optimize the adsorption strength of oxygen reduction intermediates on Fe–N4 and also shorten the bond amplitude of Fe–N4 with incoherent vibrations. As a result, both the activity and stability of Fe–N4 sites are increased by about 60% in terms of turnover frequency and demetalation resistance. This work shows the great potential of strong electronic interactions between multiphase metal species for improvements of single-atom catalysts.

Mechanistic Insights into Selective Acetaldehyde Formation from Ethanol Oxidation on Hematite Photoanodes by Operando Spectroelectrochemistry.

This study employed operando spectroelectrochemical l and photoelectrochemical methods to investigate the charge carrier dynamics of photogenerated holes in hematite for ethanol oxidation and its possible over-oxidation. Ethanol oxidation was found to form acetaldehyde with around 100 % initial selectivity and faradaic efficiency. The overoxidation of acetaldehyde was suppressed by being unable to kinetically compete with ethanol oxidation in terms of turnover frequency by a factor of ten. Temperature-dependent rate law analyses were applied to determine the activation energies of these two oxidations. For the ethanol oxidation, the activation energy was 195 meV, compared to 398 meV for acetaldehyde oxidation. These results were correlated with the valence band potential to elucidate the advantage of using hematite for safer and sustainable value-added aldehyde synthesis compared to the industrial method. The dynamics of ethanol oxidation also addressed the challenges in broad-spectrum deep oxidation of organic compounds in water purification using metal oxides.

Insights into the directions to increase turnover frequency and turnover number during photochemical water oxidation with molecular Ru catalysts

Four novel and three known mono Ru water oxidation catalysts were prepared and their photocatalytic performances in terms of turnover frequency (TOF) and turnover number (TON) were analyzed, and new directions to increase TOF and TON were presented.

A cleaner route of biodiesel production from waste frying oil using novel potassium tin oxide catalyst: A smart liquid-waste management.

The valorization of waste frying oil (WFO) to biodiesel has been carried out via solid base catalyzed transesterification reaction. A novel potassium tin oxide (KSO) catalyst was synthesized via polymer precursor auto combustion method. The catalyst showed the best physicochemical properties when it was calcined at 800°C. Using KSO 800 catalyst, the highest FAME conversion (99.5%) of WFO found at moderated reaction condition within very short time (35min); moreover, no leaching of K-species was observed in reusability test upto 5th cycle. Kinetics proved that the above catalytic reaction followed pseudo-first-order kinetics and the rate of the reaction was doubled with increasing 10°C reaction temperature. The reaction activation energy, enthalpy of activation, entropy of activation, and Gibb's free energy of activation of the reaction were found to be 66.52kJ/mol, 62.95kJ/mol, -74.07J/mol/K and 88kJ/mol respectively. Evaluation of the green parameters revealed that KSO 800 catalyzed transesterification process approached a cleaner route with excellent efficacy in terms of turnover frequency and yield. KSO 800 helped to produce high quality biodiesel from WFO adopting faster and greener reaction pathway. Thus, KSO 800 was considered as a potential and green catalyst for transforming waste oil into biofuel.

Solvent‐free oxidation of straight‐chain aliphatic primary alcohols by polymer‐grafted vanadium complexes

AbstractOxidovanadium(IV) complexes [VO(tertacac)2] (1), [VO(dipd)2] (2), and [VO(phbd)2] (3) were synthesized by reacting [VO(acac)2] with 2,2,6,6‐tetramethyl‐3,5‐hepatanedione, 1,3‐diphenyl‐1,3‐propanedione, and 1‐phenyl‐1,3‐butanedione, respectively. Imidazole‐modified Merrifield resin was used for the heterogenization of complexes 1–3. During the process of heterogenization, the V4+ center in complex 2 converts into V5+, whereas the other two complexes 1 and 3 remain in the oxidovanadium(IV) state in the polymer matrix. Theoretically, calculated IPA values of 1–3 suggest that 2 is prone to oxidation compared with 1 and 3, which was also supported by the absence of EPR lines in 5. Polymer‐supported complexes Ps‐Im‐[VIVO(tertacac)2] (4), Ps‐Im‐[VVO2(dipd)2] (5), and Ps‐Im‐[VIVO(phbd)2] (6) were applied for the solvent‐free heterogenous oxidation of a series of straight‐chain aliphatic alcohols in the presence of H2O2 at 60°C and showed excellent substrate conversion specially for the alcohols with fewer carbon atoms. Higher reaction temperature improves the substrate conversion significantly for the alcohols containing more carbon atoms such as 1‐pentanol, 1‐hexanol, and 1‐heptanol while using optimized reaction conditions. However, alcohols with fewer carbon atoms seem less affected by reaction temperatures higher than the optimized temperature. A decreasing trend in the selectivity(%) of carboxylic acid was observed with increasing carbon atoms among the examined alcohols, whereas the selectivity towards aldehydes increased. The order of efficiency of the supported catalysts is 4 &gt; 6 &gt; 5 in terms of turnover frequency (TOF) values and substrate conversion, further supported by theoretical calculations.

The Hydrogen-Storage Challenge: Nanoparticles for Metal-Catalyzed Ammonia Borane Dehydrogenation.

Dihydrogen is one of the sustainable energy vectors envisioned for the future. However, the rapidly reversible and secure storage of large quantities of hydrogen is still a technological and scientific challenge. In this context, this review proposes a recent state-of-the-art on H2 production capacities from the dehydrogenation reaction of ammonia borane (and selected related amine-boranes) as a safer solid source of H2 by hydrolysis (or solvolysis), catalyzed by nanoparticle-based systems. The review groups the results according to the transition metals constituting the catalyst with a mention to their current cost and availability. This includes the noble metals Rh, Pd, Pt, Ru, Ag, as well as cheaper Co, Ni, Cu, and Fe. For each element, the monometallic and polymetallic structures are presented and the performances are described in terms of turnover frequency and recyclability. The structure-property links are highlighted whenever possible. It appears from all these works that the mastery of the preparation of catalysts remains a crucial point both in terms of process, and control and understanding of the electronic structures of the elaborated nanomaterials. A particular effort of the scientific community remains to be made in this multidisciplinary field with major societal stakes.

Primary factors affecting denitrification efficiency of V-based catalysts in low-temperature selective catalytic reduction using NH3

The denitrification efficiency of vanadium-based catalyst for low-temperature selective catalytic reduction (SCR) using NH3 (<200 °C) highly depends on the structural species of vanadium oxide (VOx) and the physicochemical properties of the catalyst. In this study, we investigated the main factors affecting the denitrification efficiency of low-temperature NH3-SCR by adjusting synthetic factors such as calcination temperature and vanadium to oxalic acid (OA) ratio during the V/TiO2 synthesis. The main factors for enhancing the activity of low-temperature NH3-SCR with vanadium-based catalysts were identified to be (1) a high proportion of well dispersed monomeric VOx species (57.3%); (2) a large number of NH3-Lewis acid sites; and (3) a high oxygen mobility (surface adsorbed oxygen). In particular, the surface adsorbed oxygen species (Oα) of the catalyst was identified as a reactive factor in low-temperature NH3-SCR, which enhances the oxygen mobility of V/TiO2 in terms of turnover frequency (TOF). The NH3-Lewis acid sites significantly contribute to promoting the activity of low-temperature NH3-SCR at 180 °C owing to the strong adsorption strength of NH3 at a slow reaction rate.

High-throughput screening and rational design to drive discovery in molecular water oxidation catalysis

The difficulty of the oxygen evolution reaction (OER) is a fundamental impediment to the sustainable production of hydrogen, in which molecular catalysts show the most impressive activity in terms of turnover frequency. Here, we interrogate 444 automatically generated molecular water oxidation catalysts composed of well-known ligand scaffolds and 6 different transition metals (Cr, Mn, Fe, Ru, Co, and Ni). These data confirm the method-independent universal scaling relationship for water oxidation catalysts, describe routes toward circumventing this relationship, and justify the ascendency of Ru catalysts for this reaction. Leveraging this information while applying catalyst design principles, we summarize experimental results, giving credence to our prediction of 9 earth-abundant molecular catalysts with theoretical overpotentials ranging from 200 to 400 mV as promising leads for experimental investigation. We also establish insights into spin-dependent scaling relations for key OER intermediates. Altogether, this work outlines the first steps toward enabling inverse design for molecular OER catalysts. Generate total of 444 OER catalysts by combining well-known ligands and low-cost metals Demonstrate functional-independent scaling relations Establish metal-specific scaling relations and their implications Identify three Cr-based complexes as promising molecular OER catalysts Green hydrogen production could see widespread adoption if cost-effective catalysts for the oxygen evolution reaction were developed. Here, Craig et al. report a high-throughput screening of complexes generated by combining established ligands and low-cost metals, thereby identifying candidate catalysts for experimental realization and providing guidance for future studies.

Palladium-Incorporated α-MoC Mesoporous Composites for Enhanced Direct Hydrodeoxygenation of Anisole

Hydrodeoxygenation (HDO) is one of the promising catalytic routes for converting biomass derived molecules to high value products. A key step of HDO is the cleavage of an aromatic C–O bond to accomplish the deoxygenation step, however, which is energetically unfavorable. Herein, we report a series of palladium (Pd)-incorporated α-phase of molybdenum carbide (α-MoC) mesoporous composites for enhanced HDO activity of a biomass model molecule, anisole. The catalysts, x%Pd/α-MoC (x% is the molar ratio of Pd/Mo), were investigated by X-ray diffraction (XRD), temperature programmed reduction (TPR), temperature programmed desorption (TPD), Brunauer–Emmett–Teller (BET), Raman, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) techniques. Pd is highly dispersed on α-MoC when x% ≤ 1%, but aggregate to form nanoparticles when x% = 5%. The x%Pd/α-MoC catalysts (x% ≤ 1%) show enhanced HDO activity in terms of turnover frequency (TOF) and apparent activation energy barrier (Ea) compared with α-MoC and β-Mo2C catalysts. The TOF of 1%Pd/α-MoC catalyst at 160 °C is 0.115 h−1 and the Ea is 48.2 kJ/mol. Moreover, the direct cleavage of aromatic C–O bond is preferred on 1%Pd/α-MoC catalyst. The enhanced HDO activity is attributed to superior H2 dissociation ability by the highly dispersed Pd sites on carbide. This work brings new insights for rational design of the catalyst for selective C–O bond activation.

Novel Fabrication of Photoactive CuO/HY Zeolite as an Efficient Catalyst for Photodecolorization of Malachite Green

Copper oxide loaded on HY zeolite (CuO/HY) catalyst was prepared via a facile electrochemical method, and its photoactivity was evaluated by the decolorization of malachite green (MG) under fluorescent light irradiation. The physicochemical properties of catalysts were characterized by X-ray diffraction (XRD), nitrogen (N2) adsorption–desorption, 27Al and 29Si magic-angle-spinning nuclear magnetic (MAS NMR), transmission electron microscopy (TEM), Fourier transform infra-red spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS). The results showed that CuO nanoparticles are well-distributed on HY support. Besides, the isomorphous substitution of Al3+ with Cu2+ was occurred to form Si–O–Cu bond, as confirmed by the 27Al and 29Si MAS NMR, FTIR and XPS analysis. The catalyst activity towards on decolorization of MG was ranked in the following order: 3 wt% CuO/HY (99%) > 5 wt% CuO/HY (86%) > 1 wt% CuO/HY (80%) > HY (41%) > CuO (17%). The highest decolorization by 3 wt% CuO/HY is due to the well distribution of CuO nanoparticles on the HY surface of as well as the Cu incorporated into HY frameworks. In terms of turnover frequency, the 1 wt% CuO/HY showed a higher value (7.95 × 10−4 min−1) compared to the 3 wt% CuO/HY (3.13 × 10−4 min−1) and 5 wt% CuO/HY (1.64 × 10−4 min−1). The decreased of chemical oxygen demand demonstrated that the relationship between decolorization and degradability exists. A kinetic study indicated that the photocatalytic process follows a pseudo-first-order kinetics represented by the Langmuir–Hinshelwood model with the rate determining step as a surface reaction.

Nickel-Containing Ceria-Zirconia Doped with Ti and Nb. Effect of Support Composition and Preparation Method on Catalytic Activity in Methane Dry Reforming.

Nickel-containing mixed ceria-zirconia oxides also doped by Nb and Ti have been prepared by a citrate route and by original solvothermal continuous flow synthesis in supercritical alcohols. Nickel was subsequently deposited by conventional insipient wetness impregnation. The oxides are comprised of ceria-zirconia solid solution with cubic fluorite phase. Negligible amounts of impurities of zirconia are observed for samples prepared by citrate route and doped by Ti. Supports prepared by supercritical synthesis are single-phased. XRD data, Raman, and UV-Vis DR (diffuse reflectance) spectroscopy suggest increasing lattice parameter and amount of oxygen vacancies in fluorite structure after Nb and Ti incorporation despite of the preparation method. These structural changes correlate with the catalytic activity in a methane dry reforming reaction. Catalysts synthesized under supercritical conditions are more active than the catalysts of the same composition prepared by the citrate route. The catalytic activity of samples doped with Ti and Nb is two times higher in terms of TOF (turnover frequency) and increased stability of these catalysts is attributed with the highest oxygen mobility being crucial for gasification of coke precursors.

Zr–Ce-incorporated Ni/SBA-15 catalyst for high-temperature water gas shift reaction: Methane suppression by incorporated Zr and Ce

SBA-15 supports with incorporated Zr and/or Ce were synthesized using direct hydrothermal synthesis, followed by ammonia evaporation to prepare Ni–phyllosilicate-derived catalysts. The effect of zirconium and cerium ions present in the silica framework in catalyzing the high-temperature water–gas shift (WGS) reaction and circumventing the undesired methanation reaction was investigated over the temperature range from 250 to 500 °C. Diffuse-reflectance infrared Fourier transform spectroscopy revealed that surface hydroxyl species on silica were involved in promoting WGS activity for all catalysts. Furthermore, the presence of Zr and Ce in the silica framework could minimize the formation of Ni subcarbonyl species and enhance the adsorption of CO on Ni. At 375 °C, the Ni/Zr–Ce-SBA-15 catalyst achieved excellent catalytic activity in the WGS reaction in terms of turnover frequency (4.57 s−1) and hydrogen formation rate (534 μmol H2 g−1s−1). A dual-site carboxyl mechanism was proposed to be the plausible pathway over the Ni/Zr–Ce-SBA-15 catalyst.

Selective production of green solvent (isoamyl acetate) from fusel oil using a sulfonic acid-functionalized KIT-6 catalyst

Isoamyl acetate production from fusel oil was demonstrated in a heterogeneous system using sulfonated mesoporous silica KIT-6 catalysts. These were prepared by co-condensation at different 3-mercaptopropyl(methyl)dimethoxysilane (MPMDS):tetraethoxysilane (TEOS) ratios and subsequent oxidation (x-SO3H-KIT-6, where x is the molar ratio of MPMDS). Isoamyl acetate production was performed via esterification of fusel oil with acetic acid in a batch reactor at different reaction temperatures and reaction times. The optimal conditions were: 80 °C, 3 h, catalyst loading of 5 wt.%, and a 2:1 (v/v) acetic acid:fusel oil ratio. Under these conditions, a 95% yield of isoamyl acetate was achieved. The efficiency in terms of turnover frequency (TOF) was strongly affected by the number and accessibility of the acid sites, and therefore by the MPMDS:TEOS ratio. The highest yield was found for 0.3-SO3H-KIT-6, while 0.1-SO3H-KIT-6 had the highest TOF. The 0.3-SO3H-KIT-6 catalyst also exhibited excellent reusability over four cycles, with only a small reduction in isoamyl acetate yield in each cycle. Overall, the 0.3-SO3H-KIT-6 catalyst exhibited catalytic activity comparable to that of a commercial esterification catalyst. This novel catalyst has potential practical applications in selective production of isoamyl acetate.