Conventional Impregnation Method Research Articles

Effect of the synthesis method on the performance of Ni-CeO2-ZrO2 catalysts for the hydrogenolysis of glycerol with endogenous hydrogen

In this work, we investigated the influence of the synthesis method of Ni-based CeZr catalysts on their physico-chemical and catalytic properties in the hydrogenolysis (HDO) of glycerol with H2 in-situ produced by the aqueous-phase reforming (APR). Conventional impregnation method involved surface nickel deposition (NiCeZr-IM). The one-pot methods, which involved nickel embedment into CeZr lattice, included sol-gel (NiCeZr-SC) and coprecipitation (NiCeZr-CA and ultrasound-assisted NiCeZR-CS) methods. Differences in textural, structural, morphological, redox, and surface properties, together with and catalytic performance in the glycerol APR-HDO, were investigated systematically. As well, spent catalysts were deeply characterized. There were notable differences among textural properties, which significantly affected their activity in glycerol conversion. The structural characterization confirmed the successful integration of Ni into the CeZr lattice, especially for the catalysts synthesized using one-pot methods. One-pot synthesized catalysts showed stronger Ni-CeZr interaction, which affect the reducibility. The catalysts prepared by coprecipitation contained the highest metal-to-acid ratio, making them very active for C-O bond hydrogenation. Post-reaction characterization discloses a leaching of the nickel, in greater amount for both coprecipitated catalysts. This study revealed the potential of Ni-based catalysts derived from subsurface insertion of nickel into the CeZr matrix for the hydrogenolysis of glycerol without external hydrogen.

Identification of active sites for preferential oxidation of CO over Ru/TiO2 catalysts via tuning metal–support interaction

Preferential oxidation of CO (CO-PROX) is promising to purify H2 resources for proton-exchange membrane fuel cells with the challenges of identifying active sites and developing efficient catalysts. Herein, we report the high CO-PROX performance of Ru/TiO2 catalysts prepared by chemical-reduction method. The kinetic results reveal that the CO-PROX mechanism over the Ru/TiO2 catalysts follows the Langmuir-Hinshelwood model. We discover that Ruδ+ sites are more active for O2 activation and CO oxidation, while Ru0 sites prefer CO methanation in CO-PROX. The enhanced metal–support interaction (MSI) induces the formation of flat Ru nanoparticles, thereby increasing the number of interfacial Ruδ+ sites. Especially, compared with the conventional catalyst prepared by conventional wetness impregnation method, the as-synthesized RuTi-CR-R200 catalyst with strengthened MSI exhibits about 27 and 13 times higher reaction rate and intrinsic activity, respectively, for CO-PROX. To the best of our knowledge, our catalyst surpasses the catalytic performance of the reported Ru-based catalysts, and achieves 100% CO conversion in the wide temperature range of 90–150 °C, as well as high stability.

Dry Reforming of Methane over Ni-Supported SBA-15 Prepared with Physical Mixing Method by Complexing with Citric Acid

Ni-supported SBA-15 catalysts were prepared by physical mixing of Ni(NO3)2·6H2O and SBA-15 (Ni/SBA-15-M) and in the presence of citric acid as the complexing agent (Ni/SBA-15-M-C). Moreover, an Ni-supported SBA-15 catalyst was also prepared by the conventional incipient impregnation method (Ni/SBA-15-I). All the catalysts were systematically evaluated for carbon dioxide reforming of methane (CDR) at CO2/CH4 = 1.0, gas hourly space velocity of 60,000 mL·g−1·h−1, and reaction temperature of 700 °C. The characterization results show that the Ni particle size of Ni/SBA-15-M-C is significantly smaller than that of Ni/SBA-15-M due to the coordination effect of citric acid and Ni2+. Consequently, the Ni/SBA-15-M-C exhibits superior anti-coking and anti-sintering during the CDR-operated period because of the higher Ni dispersion and stronger Ni–support interaction. Compared to the Ni/SBA-15-I, the physical mixing of nickel salt and mesoporous material for preparing of Ni-based catalyst is easy to operate, although the crystal size and catalytic performance of Ni/SBA-15-C are very similar to that of Ni/SBA-15-M-I. Thus, the efficient and easily controlled catalyst structure makes the physical mixing strategy very promising for preparing highly active and stable CDR catalysts.

AlCl3 modified Pd/Al2O3 catalyst for enhanced anthraquinone hydrogenation

Anthraquinone hydrogenation to produce H2O2 is an economically interesting reaction with great industrial importance. Here, we report a series of Pd/xAl catalysts with different AlCl3 contents by a conventional stepwise impregnation method. The optimal Pd/1.0Al catalyst exhibits a higher performance toward anthraquinone hydrogenation with 8.3 g·L−1 hydrogenation efficiency, 99.5% selectivity and good stability, obviously superior to that of Pd/Al2O3 catalyst (5.2 g·L−1 and 97.2%). Detailed characterization demonstrates that AlCl3 can be grafted on the γ-Al2O3 support to obtain a modified support with abundant surface weak acid and Lewis acid, which can adsorb and activate anthraquinone. Meanwhile, its steric hindrance could isolate and disperse active metals to form more active sites. The synergies between metal sites and acid sites promotes the anthraquinone hydrogenation. Furthermore, the good stability after grafting AlCl3 could attribute to the enhanced metal-support interaction inhibiting metal particles agglomeration and leaching.

Catalytic partial oxidation of methane over bimetallic Ru–Ni supported on CeO2 for syngas production

Methane (CH4) is the second most abundant greenhouse gas (GHG) after carbon dioxide (CO2) and is widely recognized as one of the most destructive GHGs, exerting negative impacts on the Earth's atmosphere. In order to effectively reduce CH4 emissions, the conversion of methane into synthesis gas, which is a mixture of hydrogen (H2) and carbon monoxide (CO), has emerged as an appealing approach. Recent advancements have demonstrated that catalytic partial oxidation of methane (POM) holds great promise as a reaction pathway for syngas production. Here we study a series of catalysts consisting of monometallic Ru and Ni, and bimetallic Ru–Ni supported on CeO2. These catalysts were synthesized using both mechanochemical and conventional incipient wetness impregnation methods. Various preparation parameters were investigated, including the Ru:Ni metal ratio, the order of metal addition, and the milling energy and time for the mechanochemically prepared samples. The catalysts were subjected to low-temperature POM (350–600 °C) experiments to evaluate their performance. The experimental results reveal that the bimetallic Ru–Ni/CeO2 catalysts exhibit superior catalytic activity and stability compared to the monometallic Ru–CeO2 and Ni–CeO2 catalysts. Notably, the bimetallic Ru–Ni/CeO2 catalysts prepared through ball milling demonstrate a significantly lower temperature requirement for syngas production compared to the conventional catalysts prepared via incipient wetness impregnation.

CuO/CeO2 catalysts prepared by modified impregnation method for ethyl acetate oxidation

The impregnation method is one of the most popular methods for preparing various types of supported catalysts. However, the preparation of highly active catalysts by the conventional impregnation method is still a great challenge. In this paper, a modified impregnation method (MI) was developed to prepare CuO/CeO2 catalysts for the catalytic oxidation of ethyl acetate (EA). It was found that the 5 %CuO/CeO2 catalyst (5-MI-500) prepared by MI method achieves 100% EA conversion at a low temperature of 200 °C. However, the temperature for 100% EA conversion over the 5 %CuO/CeO2 catalyst prepared by the conventional method is as high as 300 °C. Notably, the 5-MI-500 catalyst exhibits the highest proportion of well-dispersed CuO and Cu-O-Ce structures, which synergistically enhance catalyst activity. The well-dispersed CuO particles enhance the redox ability of the catalyst, while the Cu-O-Ce structure provides high activated oxygen via oxygen vacancy and better thermal stability during catalytic reaction. Accordingly, the possible reaction mechanism over the 5-MI-500 catalyst for EA oxidation was proposed. This study demonstrates that the MI method reported in this paper can provide a feasible methodology to prepare highly active catalysts with unique structures.

Ultra-flexible Al2O3 fibers: A novel catalyst support material for sustainable catalysis

Flexible aluminum oxide (Al2O3) fibers were prepared by the blow spinning method and their potential as a high-temperature catalyst support was investigated. The synthesized Al2O3 fibers exhibited remarkable flexibility in both mechanical compression and recovery tests, which remained intact in a wide temperature range from −196 °C to 1200 °C. Moreover, their low thermal conductivity of 0.030 W K−1∙m−1, demonstrated an outstanding thermal insulation. Subsequently, nickel nanoparticles were uniformly distributed on the surface of the Al2O3 fibers as a self-supporting catalyst using a conventional impregnation method. The resulting self-supporting Ni/Al2O3 catalyst demonstrated remarkable thermo-catalytic performance and re-activation capability at high temperatures for thermocatalytic reaction of dry reforming of methane (DRM). Our findings highlight the potential of pure Al2O3 flexible fibers as a versatile material for various industrial applications, including high-temperature catalysis.

Cu and Cu-Fe Bi-Metal Nanoparticles Encapsulated in Hollow S-1 Zeolite for Reverse Water Gas Shift Reaction

The hollow hierarchical structure Cu@S and CuFe0.5@S catalysts were successfully synthesized through the “dissolution-recrystallization” (D-R) method for the reverse water gas shift reaction (RWGS). The encapsulated catalysts had a hierarchical porous structure and better dispersion of Cu particles than the Cu-S and CuFe0.5-S samples prepared via the conventional impregnation method. Furthermore, CuFe0.5-S and CuFe0.5@S catalysts showed higher CO2 conversion and 100% selectivity of CO at the entire temperature range investigated in this work compared to the monometallic catalysts Cu-S and Cu@S. Interestingly, the reaction activity of all the samples increased according to the sequence: CuFe0.5@S > CuFe0.5-S > Cu@S > Cu-S at 400–550 °C under atmospheric pressure. These results indicate that the higher dispersion of encapsulation structure and the enhanced surface basicity derived from the addition of Fe play crucial roles in enhancing the catalytic performance of Cu-based catalysts in the RWGS reaction.

Modification of Copper-Ceria Catalyst via Reverse Microemulsion Method and Study of the Effects of Surfactant on WGS Catalyst Activity

Some major drawbacks encountered in the synthesis of copper-ceria (Cu-CeO2)-based Water Gas Shift (WGS) catalyst via the conventional Impregnation (IMP) method are aggregate formation and nanoparticles’ instability. These lead to the poor interaction between Copper and Ceria, thereby impeding the catalytic activity with the inefficient utilization of active sites. To overcome these drawbacks, in this study, we described the synthesis of the Cu-CeO2 catalyst via the Reverse Microemulsion (RME) method with the help of the organic surfactant. This development of insights and strategies resulted in the preparation of porous particles with uniform size distribution and improved interaction within the composites, which were evident through XRD, XPS, BET Surface area, TPR, TEM and SEM analysis results. Remarkably, the optimum 20% Cu-CeO2 catalyst prepared by RME method was found to have superior Water Gas Shift (WGS) catalytic activity than the conventionally Impregnated catalyst when their CO conversion efficiencies were tested in WGS reaction at different feed gas compositions with and without CO2. Moreover, the 20% Cu-CeO2 sample prepared by RME method exhibited sustained catalytic activity throughout the entire 48 h period without any signs of deactivation. This observation highlights RME method as the potential pathway for developing more effective nanoparticle catalysts for hydrogen production, contributing to the growing demand for clean and sustainable energy sources.

Synthesis of cyclodextrin-stabilized gold nanoparticles supported hierarchical zeolites for the facile production of furandicarboxylic acid (FDCA) from 5-hydroxymethylfurfural (HMF)

The development of gold nanoparticles (Au NPs)-based catalysts is a crucial issue in diverse catalytic applications due to their excellent activity. However, it often suffers from the Au NPs sintering at high temperatures, and therefore the aggregation of Au NPs to large particle sizes results in a decreased active surface area, eventually lowering a catalytic activity. To overcome these limitations, the rational design of small-scale and highly dispersed nanoparticles of gold on oxide supports is a challenging task in heterogeneous catalysis. In this contribution, we report an efficient concept to fabricate ultra-small gold nanoparticles supported on hierarchical ZSM-5 surfaces using cyclodextrin as a stabilizer with the particle size in the range of 1.3 ± 0.4 nm. In strong contrast to this, the large gold particles on zeolite surfaces are obtained approximately 3.6 ± 3.2 nm, when using a conventional impregnation method without a stabilizer. Consequently, the rationally designed ultra-small gold nanoparticles supported on hierarchical ZSM-5 can greatly promote high catalytic performance in HMF oxidation to FDCA with a yield of 75% under mild reaction condition. These findings emphasize the advantage of using cyclodextrin stabilized metallic nanoparticles supported on zeolite surfaces as heterogeneous catalysts for biomonomer production. This example opens up perspectives for the development of highly efficient catalytic materials of gold nanoparticle-zeolite interfaces for biorefinery applications.

Comparative Studies on Effects of Metal Cation (La) and Non-Metal Anion (N) Doping on CeO2 Nanoparticles for Regenerative Scavenging of Reactive Oxygen Radicals

The intrinsic effects of metal cation (La) and non-metallic anion (N) doping of CeO2 nanoparticles (NPs) for regenerative scavenging of reactive oxygen radicals were studied. La-doped CeO2 NPs were prepared by the conventional impregnation method at various La doping levels. N-doped CeO2 NPs were prepared by urea thermolysis with two different methods: (i) direct thermolysis of urea after physical mixing with CeO2 NPs and (ii) wet impregnation of CeO2 NPs with urea followed by thermolysis under inert N2 atmosphere. Physicochemical properties of samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and N2 sorption measurement. Radical scavenging properties of the samples were characterized by applying Fenton’s reaction. Results indicated that atomic N doping on CeO2 NPs significantly enhanced radical scavenging properties of CeO2 NPs, resulting in an activity of N-doped CeO2 about 3.6 times greater than the pristine CeO2 NPs and 1.6 times higher than the La-doped CeO2 NPs. This result suggests that anionic N doping of CeO2 NPs is highly effective in enhancing radical scavenging properties of CeO2 NPs, whereas such modifications have been typically practiced by hetero-metal doping with rare earth metal elements. A collective structure–property correlation analysis suggested that enhancement of radical scavenging properties of heteroatom-doped CeO2 NPs was largely attributed to an increase in surface oxygen vacancies on CeO2 NPs due to heteroatom doping.

Na-modified carbon nitride as a leach-resistant and cost-effective solid base catalyst for biodiesel production

Na-modified graphitic carbon nitrides were utilized for the transesterification of soybean oil and methanol. Graphitic carbon nitrides have not yet been widely applied in biodiesel production, despite their chemical stability and basicity. The catalysts were obtained via the co-thermal polymerization of NaOH and melamine. Catalyst prepared using conventional impregnation method was applied for comparison. The copolymerized catalyst with the optimum Na content showed over 90% biodiesel yield for 10 repeated cycles. The prepared catalysts were characterized by Fourier transform infrared spectrometry, X-ray diffraction, scanning electron microscopy/energy dispersive X-ray spectroscopy, CO2-diffuse reflectance infrared Fourier transform spectroscopy, and X-ray photoelectron spectroscopy. The elaborate rigid bonds between Na and N contributed to the leaching-resistance and catalytic activity. While the majority of Na species in impregnated catalysts existed in the form of Na-O, which was easily leached out to the reaction medium showing rapid catalyst deactivation over the repeated cycles. The basicity derived from the electron transfer from the Na to N atoms was confirmed from the density functional theory and CO2-diffuse reflectance infrared Fourier transform spectroscopy.

Photodeposition of Fe-Based Cocatalysts Capable of Effectively Promoting the Oxygen Evolution Activity of BaTaO2N

Activation of narrow bandgap photocatalysts is a prerequisite for the efficient production of renewable hydrogen from water using sunlight. Loading of dual cocatalysts intended to promote reduction and oxidation reactions by photodeposition is known to greatly enhance the water splitting activity of certain oxide photocatalysts. However, it is difficult to photodeposit oxygen evolution cocatalysts onto narrow bandgap oxynitride photocatalysts because the driving forces for the necessary oxidation reactions are weak. The present work demonstrates oxidative photodeposition of the Fe-based cocatalyst FeOx onto a Mg-doped BaTaO2N photocatalyst having an absorption edge wavelength of 620 nm. This modification enhances the oxygen evolution activity of the photocatalyst more effectively than conventional impregnation methods. The rapid removal of photoexcited electrons from the photocatalyst by a reduction cocatalyst (Pt) and an electron acceptor (molecular oxygen) are evidently necessary for the photodeposition of the FeOx cocatalyst. A Mg-doped BaTaO2N photocatalyst coloaded with Pt and FeOx exhibits an apparent quantum yield of 1.2% at 420 nm during the oxygen evolution reaction in an aqueous AgNO3 solution. This photodeposition procedure does not involve any heat treatment and so provides new opportunities for the design and construction of oxygen evolution sites on narrow-bandgap non-oxide photocatalysts that may be prone to thermal decomposition.

Heterogenous Iron Oxide Assemblages for Use in Catalytic Ozonation: Reactivity, Kinetics, and Reaction Mechanism.

Heterogeneous catalytic ozonation (HCO) has gained increasing attention as an effective process to remove refractory organic pollutants from industrial effluents. However, widespread application of HCO is still limited due to the typically low efficacy of catalysts used and matrix passivation effects. To this end, we prepared an Al2O3-supported Fe catalyst with high reactivity via a facile urea-based heterogeneous precipitation method. Due to the nonsintering nature of the preparation method, a heterogeneous catalytic layer comprised of γ-FeOOH and α-Fe2O3 is formed on the Al2O3 support (termed NS-Fe-Al2O3). On treatment of a real industrial effluent by HCO, the presence of NS-Fe-Al2O3 increased the removal of organics by ∼100% compared to that achieved with a control catalyst (i.e., α-Fe2O3/Al2O3 or γ-FeOOH/Al2O3) that was prepared by a conventional impregnation and calcination method. Furthermore, our results confirmed that the novel NS-Fe-Al2O3 catalyst demonstrated resistance to the inhibitory effect of high concentration of chloride and sulfate ions usually present in industrial effluent. A mathematical kinetic model was developed that adequately describes the mechanism of HCO process in the presence of NS-Fe-Al2O3. Overall, the results presented here provide valuable guidance for the synthesis of effective and robust catalysts that will facilitate the wider industrial application of HCO.

Novel Impregnation-Deposition Method to Synthesize a Presulfided MoS2/Al2O3 Catalyst and Its Application in Hydrodesulfurization.

A novel impregnation-deposition method was applied to prepare presulfided MoS2/Al2O3 catalysts with large surface areas for the application of hydrodesulfurization (HDS). The synthesized catalysts were characterized systematically, and their catalytic performances were evaluated by the HDS of dibenzothiophene (DBT). It is found that the impregnation-deposition method improves the surface area of the synthesized catalysts by eliminating the micropores of the alumina support and adding mesostructured MoS2 particles within the support. Moreover, this method enhances the reducibility of the sulfided Mo species, as characterized by temperature-programed reduction (TPR) and X-ray photoelectron spectroscopy. Compared to the impregnation method, the impregnation-deposition method leads to the formation of more active sites as proved by TPR and CO-Fourier-transform infrared analyses. Hence, the reaction conversion rates and the hydrogenation/direct-desulfurization ratios of the DBT on the catalysts synthesized by the impregnation-deposition method are 1.3 times and 1.5 times as high as those of the catalysts made by the conventional impregnation method, respectively.

Surfactant-assisted impregnation of SBA-15 with highly dispersed copper species for CO oxidation

Copper containing SBA-15 materials has been prepared through a facile surfactant-assisted impregnation method. The surfactant contained in as-synthesized SBA-15 plays an important role to facilitate the distribution of copper species into the channels. The obtained materials have been fully characterized by several different techniques and the results show that the surfactant-assisted impregnation method is superior to the conventional impregnation method for obtaining Cu-SBA-15 with highly dispersed copper species which are mainly exist as isolated copper species and small clusters. The products exhibit superior CO oxidation activity and stability compared with that of Cu-SBA-15 prepared through the conventional wet impregnation method owning to the more finely dispersed Cu species and active sites.

Facile formation of barium titanium oxyhydride on a titanium hydride surface as an ammonia synthesis catalyst.

Oxyhydrides are promising compounds as supports for ammonia synthesis catalysts because they suppress hydrogen poisoning on the catalyst surface and enhance the ammonia synthesis activity. Herein, we developed a facile method for preparing BaTiO2.5H0.5, a perovskite oxyhydride, on a TiH2 surface via the conventional wet impregnation method using TiH2 and Ba hydroxide. Scanning electron microscopy and high-angle annular dark-field scanning transmission electron microscopy observations revealed that BaTiO2.5H0.5 crystallized as nanoparticles of ca. 100-200 nm on the TiH2 surface. The Ru-loaded catalyst Ru/BaTiO2.5H0.5-TiH2 exhibited 2.46 times higher ammonia synthesis activity (3.05 mmol-NH3 g-1 h-1 at 400 °C) than the benchmark Ru catalyst Ru-Cs/MgO (1.24 mmol-NH3 g-1 h-1 at 400 °C) because of the suppression of hydrogen poisoning. The analysis of reaction orders showed that the effect of suppressing hydrogen poisoning on Ru/BaTiO2.5H0.5-TiH2 was equivalent to that of the reported Ru/BaTiO2.5H0.5 catalyst, thus supporting the formation of BaTiO2.5H0.5 perovskite oxyhydride. This study demonstrated that the selection of appropriate raw materials facilitates the formation of BaTiO2.5H0.5 oxyhydride nanoparticles on the TiH2 surface using the conventional synthesis method.

Preparation of highly dispersed SnO/TiO2 catalysts and their performances in catalyzing polyol ester.

A series of stannous oxide supported on rutile titanium dioxide (SnO/TiO2) were prepared by a conventional incipient wetness impregnation method, and their performance as catalysts for fatty acid esterification reactions was investigated. The effects of Sn precursors (SnCl2·2H2O or SnC2O4), loading amounts (5-15%), and treating ambiences (air and N2) were explored. The optimized 10% SnO/TiO2-Cl with SnCl2·2H2O as the Sn precursor and thermal treatment in N2 showed the best esterification performance. Specifically, 10% SnO/TiO2-Cl catalyzed the esterification process of trimethylolpropane and n-octanoic acid with a conversion of 99.6% over 5 h at 160 °C, and 10% SnO/TiO2-Cl was efficient for six catalytic cycles. Based on the results of X-ray diffraction (XRD), Raman spectra, high-resolution transmission electron microscopy (HRTEM), infrared spectra of pyridine adsorption (Py-IR), and ammonia temperature programmed desorption (NH3-TPD), the improved catalytic performance is supposed to be attributable to the high dispersion of the Sn species on 10% SnO/TiO2-Cl as the moderate Lewis acid sites.

Bimetallic Ru–Pd supported on CeO2 for the catalytic partial oxidation of methane into syngas

A series of monometallic Ru, Pd, and bimetallic Ru–Pd catalysts loaded on CeO2 support have been prepared via mechanochemical and conventional incipient wetness impregnation methods and used in the partial oxidation of methane (POM) to obtain synthesis gas (H2 and CO). The influence of the preparation method, the order of addition of the metals, the Ru:Pd metal ratio, and the milling energy and time for samples prepared by the mechanochemical method, have been evaluated between 300 and 600 °C. The results revealed that bimetallic Ru–Pd/CeO2 catalysts outperform monometallic Ru–CeO2 and Pd–CeO2 for POM, both in terms of catalytic activity and stability. Additionally, the bimetallic Ru–Pd/CeO2 catalysts prepared by ball milling produced syngas at a much lower temperature compared to the conventional catalysts prepared by incipient wetness impregnation. Raman spectroscopy, temperature programmed reduction (H2–TPR), X–ray photoelectron spectroscopy (XPS) and high–resolution transmission electron microscopy (HRTEM) have been used to characterize the catalysts before and after reaction.

Boosting the catalytic performance of Fe/Zr catalyst by tungsten addition for selective catalytic reduction of NOx with ammonia

To clarify the effect of WO3 doping over Fe/Zr catalyst, several Fe/Zr-xW catalysts were prepared via conventional wet impregnation method, and the selective catalytic reduction (SCR) performance was studied. The Fe/Zr-0.1 W catalyst showed the highest catalytic activity and achieved nearly 100 % in a wide operating temperature window of 300–500 °C, and the N2 selectivity exceeded 90 % over the entire temperature range under a high hour space velocity of 90, 000 h−1. In addition, Fe/Zr-0.1 W catalyst also exhibited superior resistance to SO2 compared to Fe/Zr catalyst without WO3 introduction. Further characterization results indicated that the Fe/Zr-0.1 W catalyst possessed larger BET specific surface area, better dispersion of active component, higher concentration of Fe3+ and more surface chemisorbed oxygen species, which might be the predominant factors for its superior catalytic performance. More importantly, WO3 doping improved the redox capacity and surface acidity, thus promoting the redox circle and enhancing the adsorption ability of NH3. According to the transient in-situ DRIFTS experiment results, the doping of WO3 increased the L-H reaction pathway on the surface of Fe/Zr catalyst during the NH3-SCR reaction. The present work could provide a new way for developing a high-performance non-vanadium SCR catalyst in practical application.