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Pancreatitis is a common disease of digestive system, easy to deteriorate, acute onset, poor prognosis, high fatality rate. Analgesic and sedative drugs are often used to treat pancreatitis. Dexmedetomidine is an adrenergic receptor agonist, and Sufentanil is a common analgesic sedative. However, the mechanism of their combined use in the treatment of pancreatitis injury has not been fully elucidated. Wistar rat pancreatitis Model was established and randomly divided into 4 groups: Dex group, Dex+Suf group, model group and Sufentanil group. Compare and analyze heart rate, oxygen saturation, body temperature, and respiration. The onset time, duration, analgesic time and adverse reactions were recorded. Serum amylase, creatinine and alanine aminotransferase were detected. Serum IL-6 and IL-1β levels were detected, and apoptotic activity was detected by Caspase 3 activity kit. The expression of HMGB1, TLR2 and TLR4 mRNA in pancreatic tissues. Dexmedetomide alone or combined with sufentanil can improve the general indicators, sedation and analgesia time is shorter, longer duration. Serum secretion of IL-6 and IL-1β decreased, expression of HMGB1, TLR2 and TLR4 decreased, pancreatic serological serum amylase, creatinine, alanine aminotransferase activities decreased, Caspase 3 activity decreased. The curative effect of combination group was significantly higher than that of model group (p < 0.01). Dexmedetomidine combined with sufentanil can affect the expression of HMGB1/TLRs, inhibit inflammation, improve sedation and analgesia, and inhibit apoptosis, so as to alleviate the injury of acute pancreatitis.

Graphitic carbon nitride (g-C3N4) is considered a potential photoactive semiconductor for photocatalytic hydrogen evolution (PHE). Although being active in producing hydrogen, it is in general suffering from severe charge recombination rate, low mobility of charge and narrow visible light response range largely, which has restricted its greater application. Existing reviews on g-C3N4 are lacking of systematic and summative view on the effects of the physical-chemical structure-activity relationship between g-C3N4 and the modification involving phosphorus (P). Many studies indicate that adding P into g-C3N4 could effectively elevate the photo-activity. Underlying reasons for the observed improved photo-activity are discussed in this review. Here, P-containing g-C3N4 photocatalysts are grouped into the categories of P elemental doping, composite with elemental P, as well as the addition of metal phosphide as cocatalysts. These P-containing g-C3N4 possess novel properties demonstrating favorable photocatalytic activities as compared with the other elemental (such as O, S, B)-based materials. Therefore, in this mini review, we summarize and discuss the advances on the P-containing g-C3N4 photocatalysts, including the preparation strategies, physicochemical properties, the application for hydrogen production as well as the related reaction mechanism. Importantly, the physical-chemical structure-activity relationship between g-C3N4 and the integrated P is revealed. Finally, an overview of the current research status and challenges on future is presented, which would be helpful in designing and developing other P-containing photocatalysts for various photocatalytic applications.

Catalytic combustion is thought as an efficient and economic pathway to remove volatile organic compounds, and its critical issue is the development of high-performance catalytic materials. In this work, we used the in situ synthesis method to prepare the silicalite-1 (S-1)-supported Pd nanoparticles (NPs). It is found that the as-prepared catalysts displayed a hexagonal prism morphology and a surface area of 390-440 m

Bimetallic compounds are a kind of important catalytic materials in heterogeneous catalysis. In this work, we first employed n-butyllithium as reducing agent to synthesize Ir and IrFex (x is the Fe/Ir molar ratio and equal to 0.49, 0.90, and 2.80) nanocrystals (NCs), and then used an adsorption strategy to load them on the surface of ordered mesoporous ceria (meso-CeO2) derived from the KIT-6-templating route to obtain the 0.48 wt% Ir/meso-CeO2 (denoted as 0.48Ir/meso-CeO2) and 0.53–0.89 wt% IrFex/meso-CeO2 (denoted as 0.53IrFe0.49/meso-CeO2, 0.59IrFe0.90/meso-CeO2, and 0.89IrFe2.80/meso-CeO2) samples. Physicochemical properties of the samples were characterized by means of various techniques. It is shown that all of the samples possessed a cubic crystal phase, an ordered mesoporous architecture, and a surface area of 84–124 m2/g, in which the IrFex NCs with an average size of ca. 2 nm were highly dispersed on the meso-CeO2 surface. Among all of the samples, 0.59IrFe0.90/meso-CeO2 performed the best for acetylene combustion (T10% =155 °C, T50% =162 °C, and T90% =165 °C at space velocity = 20,000 mL/(g h)). Furthermore, 0.59IrFe0.90/meso-CeO2 showed good water- and carbon dioxide-resistant performance, and its partial deactivation due to the introduction of SO2 was reversible. The possible reaction mechanisms over Ir/meso-CeO2 or IrFex/meso-CeO2 were also discussed. We conclude that the well dispersed IrFe0.90 NCs, high adsorbed oxygen and acetylene amounts, low-temperature reducibility, and strong interaction between IrFe0.90 NCs and meso-CeO2 were responsible for the good catalytic performance of 0.59IrFe0.90/meso-CeO2.

The purification efficiency of auto-exhaust carbon particles in the catalytic aftertreatment system of vehicle exhaust is strongly dependent on the interface nanostructure between the noble metal component and oxide supports. Herein, we have elaborately synthesized the catalysts (Pt/Fe2O3-R) of Pt nanoparticles decorated on the hexagonal bipyramid α-Fe2O3 nanocrystals with co-exposed twelve {113} and six {104} facets. The area ratios (R) of co-exposed {113} to {104} facets in α-Fe2O3 nanocrystals were adjusted by the fluoride ion concentration in the hydrothermal method. The strong Pt-Fe2O3{113} facet interaction boosts the formation of coordination unsaturated ferric sites for enhancing adsorption/activation of O2 and NO. Pt/Fe2O3-R catalysts exhibited the Fe2O3{113} facet-dependent performance during catalytic purification of soot particles in the presence of H2O. Among the catalysts, the Pt/Fe2O3-19 catalyst exhibits the highest catalytic activities (T50 = 365 °C, TOF = 0.13 h-1), the lowest apparent activation energy (69 kJ mol-1), and excellent catalytic stability during soot purification. Combined with the results of characterizations and density functional theory calculations, the catalytic mechanism is proposed: the active sites located at the Pt-Fe2O3{113} interface can boost the key step of NO oxidation to NO2. The crystal facet engineering is an effective strategy to obtain efficient catalysts for soot purification in practical applications.

Ru-based catalysts for catalytic combustion of high-toxicity Cl-containing volatile organic compounds are inclined to produce Cl2 instead of ideal HCl due to the Deacon reaction. We herein reported that the three-dimensionally ordered macroporous (3DOM) WOx-supported RuP nanocatalyst greatly improved HCl selectivity (at 400 °C, increased from 66.0% over Ru/3DOM WOx to 96.4% over RuP/3DOM WOx) and reduced chlorine-containing byproducts for 1,2-dichloroethane (1,2-DCE) oxidation. P-doping enhanced the number of structural hydroxyl groups and Bronsted acid sites. The isotopic 1,2-DCE temperature-programmed desorption experiment in the presence of H218O indicated the generation of a new active oxygen species 16O18O that participated in the reaction. Generally, P-doping and H2O introduction could promote the exchange reaction between Cl and hydroxyl groups, rather than oxygen defects, and then benefit the production of HCl and reduce the generation of other chlorine species or Cl2, via the reaction processes of C2H3Cl → alcohol → aldehyde → carboxylic acids.

Transition metal oxides (MOx; M = Cr, Mn, Fe, Ni, Cu)-doped titania solid solution catalysts (10 wt% MOx–TiO2, denoted as 10MOx–TiO2) were prepared by the coprecipitation method. The techniques of XRD, TPR, TPD, XPS, TPSR, and in situ DRIFTS were used to characterize physicochemical properties of the materials, and their catalytic activities were evaluated for the oxidation of 1,2-dichloroethane (1,2-DCE). The introduction of MOx enhanced adsorption and activation of oxygen molecules, mobility of surface lattice oxygen, and low-temperature reducibility. The 10MOx–TiO2 catalysts showed good performance, with 10CrOx–TiO2 exhibiting the highest catalytic activity (reaction rate = 2.35 × 10−7 mol/(gcat s) and apparent activation energy (Ea) =35 kJ/mol at space velocity = 40,000 mL/(g h)) and good resistance to chlorine poisoning, The mechanism of 1,2-DCE oxidation over 10CrOx–TiO2 was also discussed based on the results of TPSR and in situ DRIFTS characterization. It is concluded that strong acidity and redox ability, high adsorbed oxygen species concentration, and strong interaction between TiO2 and CrOx were accountable for the good performance of 10CrOx–TiO2.

Three-dimensionally ordered macroporous (3DOM) MnCo2O4-supported Co3O4 and AuPd (xAuPdz/yCo3O4/3DOM MnCo2O4; x = 0.56–1.98 wt%, z = 1.9–2.1, and y = 4.80–24.36 wt%) catalysts were prepared using polymethyl methacrylate (PMMA) microsphere-templating, incipient wetness impregnation, and polyvinyl alcohol (PVA)-protected reduction methods. Physicochemical properties of the materials were characterized by means of numerous techniques, and their catalytic activities were evaluated for methane combustion. It is found that the xAuPdz/yCo3O4/3DOM MnCo2O4 samples with a surface area of 26.5–53.1 m2/g possessed a high-quality 3DOM architecture, in which the AuPd nanoparticles (NPs) with a size of 4.6–5.8 nm were highly dispersed on the surface of the macropore framework. Among all of the samples, 1.98AuPd2.1/18.20Co3O4/3DOM MnCo2O4 exhibited the highest catalytic activity: the T10%, T50%, and T90% (temperatures required for achieving methane conversions of 10, 50, and 90 %, respectively) were 262, 340, and 408 °C at a space velocity of 40,000 mL/(g h). Partial deactivation of the 1.98AuPd2.1/18.20Co3O4/3DOM MnCo2O4 sample due to introduction of water vapor or carbon dioxide was reversible. It is concluded that the good catalytic performance of 1.98AuPd2.1/18.20Co3O4/3DOM MnCo2O4 was associated with its high adsorbed oxygen species concentration, good low-temperature reducibility, and strong interaction between Co3O4 or AuPd2.1 NPs and 3DOM MnCo2O4.

The volatile organic compounds (VOCs) from cooking oil fumes are very complex and do harm to humans and the environment. Herein, we develop the high-efficiency and energy-saving synergistic photothermocatalytic oxidation approach to eliminate the mixture of heptane and hexanal, the representative VOCs with high concentrations in cooking oil fumes. The Pt/CeO

The local coordination structure of metal sites essentially determines the performance of supported metal catalysts. Using a surface defect enrichment strategy, we successfully fabricated Pt atomic single-layer (Pt

SnO2 is widely used in catalysis owing to its oxygen vacancies, reducible oxygen species, and acidity. In this work, Ru nanoparticles (NPs) supported on three-dimensionally ordered macroporous (3DOM) SnO2 (xRu/3DOM SnO2, Ru loading (x) = 0.09–1.65 wt%) were fabricated via the polyvinyl alcohol-protected reduction routes, and their catalytic activities were determined for trichloroethylene (TCE) and/or toluene oxidation. It was shown that the 0.98Ru/3DOM SnO2 sample exhibited the best activity and good thermal stability, with the temperature (T90% ) and apparent activation energy at a TCE (1000 ppmv) conversion of 90% being 300 °C and 44 kJ/mol at space velocity = 40,000 mL/(g h), respectively. Trichloromethane, carbon tetrachloride , tetrachloroethylene, and trichloroacetaldehyde hydrate were the main intermediates in TCE oxidation. The high catalytic performance of 0.98Ru/3DOM SnO 2 was attributed to the presence of hydroxyl groups adsorbed at the oxygen vacancies, strong O2 adsorption ability, good low-temperature reducibility, and strong interaction between Ru NPs and 3DOM SnO2. In addition, a catalytic mechanism over xRu/3DOM SnO2 was proposed under dry and humid conditions. The introduction of H2O could block some of the reaction pathways from inhibiting the production of C2Cl4, reduce formation of some by-products (e.g., CH2Cl2, CH3COOH, and C2H2Cl2), promote removal of the chlorine species, and generate a greater amount of HCl and a smaller amount of Cl2. Furthermore, introducing toluene into the TCE stream could generate smaller amounts of organic chlorine by-products and greater amounts of inorganic chlorine products (HCl and Cl2 ). We are sure that this work can provide a guideline for the industrial application of supported Ru catalysts in the removal of Cl-containing volatile organic compounds .

The novel La–B–O–C composites were fabricated as catalysts for methane catalytic combustion at low temperature, and considering the effect of newly C–O bond on B-site ions as active sites, three metal ions (Co, Mn, Fe) were selected for experiment. XRD, N2-physisorption, XPS and H2-TPR measurements were used to characterize the physicochemical properties of catalysts, which showed that the newly established C–O–B bond reduced the ionic valence of the B-site, and the redox capacities were increased or decreased to different degrees, respectively. Catalytic tests showed that T50 of La–Co–C–O composites (LC-C) and La–Fe–C–O composites (LF-C) are 377 °C and 482 °C, much lower than that of unmodified catalyst, respectively. But T50 of La–Mn–C–O composites (LM-C) increases to 507 °C from 493 °C. The superior performance of LC-C could be attributed to the high oxygen vacancies and enhanced redox property, and the better performance of LF-C was mainly benefited from the increase in lattice oxygen. For LM-C, the sacrifice of Mn4+ weakened the catalytic activity. There are more obvious mechanistic differences for different B-site elements in the La–B–O–C. The study will bring innovative insights into the design of excellent composites catalysts for methane oxidation.

The thermocatalytic decomposition (TCD) of methane is considered as a milestone towards the production of valuable COx-free hydrogen and carbon nanomaterials without the use of steam or O2. Previous reviews have been aimed at methane decomposition over the different catalysts, such as nickel-based catalysts, non-nickel-based catalysts, metal oxide-supported catalysts, and carbon-supported catalysts. The Ni-based catalysts are suitably applied for methane TCD process due to their high activity and low cost. However, the loss of activity and/or stability with reaction time is one of the most notable challenges in the use of Ni-based catalysts, and a number of studies on the roles of various factors in overcoming such a problem can be found in the literature. Recently, the use of the second metal as a promoter to control catalyst deactivation has attracted much attention. The present review focuses on classification of the different promoters based on the periodic table of elements, such as alkali metals, alkaline earth, transition metals, noble metals, and rare earth metals, and makes a detailed discussion on promotional roles in influencing their physicochemical properties and catalytic performance of the Ni-based catalysts. The generalized structure-performance relationship of the metals-doped catalysts may give an appreciated reference to the design of catalysts with highly pure hydrogen production and carbon nanomaterials. In addition, this review also covers the works on effects of the promoters on nature and morphology of the formed carbon nanomaterials. The use of transition metals (Fe, Co or Cu), noble metal (Pd or Pt), and rare earth metal (La) with a suitable loading as a promoter influenced performance and lifespan of the catalyst and the interaction of Ni particles with the support. Among these promoters, Cu, Pd, La, and Cu–Pd as a dopant have demonstrated superior performance, which was attributed to the capability of these elements in prohibiting carbon accumulation on the active Ni components.

The compositions of volatile organic compounds (VOCs) under actual industrial conditions are often complex; especially, the interaction of intermediate products easily leads to more toxic emissions that are harmful to the atmospheric environment and human health. Herein, we report a comparative investigation on 1,2-dichloroethane (1,2-DCE) and (1,2-DCE + toluene) oxidation over the Ru/TiO

Pt-based catalysts can be poisoned by the chlorine formed during the oxidation of multicomponent volatile organic compounds (VOCs) containing chlorinated VOCs. Improving the low-temperature chlorine resistance of catalysts is important for industrial applications, although it is yet challenging. We hereby demonstrate the essential catalytic roles of a bifunctional catalyst with an atomic-scale metal/oxide interface constructed by an intermetallic compound nanocrystal. Introducing trichloroethylene (TCE) exhibits a less negative effect on the catalytic activity of the bimetallic catalyst for

The catalyzed reduction process plays an important role in the safe handling of environmental contaminants. It is generally believed that the adsorption of pollutants and cleavage of chemical bonds...

Precious metal catalysts with superior low-temperature activity and excellent thermal stability are highly needed in environmental catalysis field. In this work, a novel two-step incipient wetness impregnation (T-IWI) method was developed for the fabrication of a unique and highly stable CeO2/Al2O3 support (CA-T). Pd anchored on CA-T exhibited a much higher low-temperature catalytic activity and superior thermal stability in carbon monoxide (CO) and hydrocarbon (HC) oxidations, compared to Pd anchored on conventional CeO2/Al2O3 (CA), which was prepared by a one-step IWI method. After aging treatment at 800 °C, the CO oxidation rate on Pd/CA-T (1.69 mmol/(gPd s)) at 120 °C was 4.1 and 84.5 times of those on Pd/CA (0.41 mmol/(gPd s)) and Pd/Al2O3 (0.02 mmol/(gPd s)), respectively. It was revealed that the CA-T support with well-controlled small CeO2 particles (ca. 12 nm) possessed abundant defects for Pd anchoring, which created rich Pd-CeO2 interfaces with strengthened interaction between Pd and CeO2 where oxygen could be efficiently activated. This resulted in the significantly improved oxidation activity and thermal stability of Pd/CA-T catalysts. The T-IWI method developed herein can be applied as a universal approach to prepare highly stable metal oxide-alumina-based supports, which have broad application in environmental catalyst design, especially for automobile exhaust aftertreatment.

Zeolites have ordered pore structures, good spatial constraints, and superior hydrothermal stability. In addition, the active metal elements inside and outside the zeolite framework provide the porous material with adjustable acid–base property and good redox performance. Thus, zeolites-based catalysts are more and more widely used in chemical industries. Combining the advantages of zeolites and active metal components, the zeolites-based materials are used to catalyze the oxidation of methane to produce various products, such as carbon dioxide, methanol, formaldehyde, formic acid, acetic acid, and etc. This multifunction, high selectivity, and good activity are the key factors that enable the zeolites-based catalysts to be used for methane activation and conversion. In this review article, we briefly introduce and discuss the effect of zeolite materials on the activation of C–H bonds in methane and the reaction mechanisms of complete methane oxidation and selective methane oxidation. Pd/zeolite is used for the complete oxidation of methane to carbon dioxide and water, and Fe- and Cu-zeolite catalysts are used for the partial oxidation of methane to methanol, formaldehyde, formic acid, and etc. The prospects and challenges of zeolite-based catalysts in the future research work and practical applications are also envisioned. We hope that the outcome of this review can stimulate more researchers to develop more effective zeolite-based catalysts for the complete or selective oxidation of methane.

A series of BUC-21/N-K2Ti4O9 composites (B1NX) were facilely fabricated from BUC-21 and N-K2Ti4O9 via ball-milling, and they were fully characterized using various techniques. The photocatalytic reduction of Cr(VI) over the B1NX composites was investigated systematically under various conditions, including different light sources, pH values, hole scavengers, and inorganic ions, in both real lake water and tap water. The BUC-21/N-K2Ti4O9 composites demonstrated remarkable photocatalytic Cr(VI) reduction performance, good reusability, and stability under both UV and white light irradiation. The introduction of N-K2Ti4O9 into BUC-21 not only broadened its light absorption region to white light, but also strongly inhibited the recombination of the photo-generated electrons and holes. Mechanisms of photocatalytic Cr(VI) reduction under both UV light and white light were proposed and verified by electrochemical measurements, active species capture experiments, and ESR measurements.

The continuous emissions of volatile organic compounds (VOCs) from the industrial process cause serious environmental problems and pose a threat to human health. Photodegradation technology and bio...

Photothermal synergistic catalytic oxidation of toluene over single-atom Pt catalysts was investigated. Compared with the conventional thermocatalytic oxidation in the dark, toluene conversion and CO

The controlled oxidation of alcohols to the corresponding ketones or aldehydes via selective cleavage of the β-C-H bond of alcohols under mild conditions still remains a significant challenge. Although the metal/oxide interface is highly active and selective, the interfacial sites fall far behind the demand, due to the large and thick support. Herein, we successfully develop a unique Au-CuO Janus structure (average particle size=3.8 nm) with an ultrathin CuO layer (0.5 nm thickness) via a bimetal in situ activation and separation strategy. The resulting Au-CuO interfacial sites prominently enhance isopropanol adsorption and decrease the energy barrier of β-C-H bond scission from 1.44 to 0.01 eV due to the strong affinity between the O atom of CuO and the H atom of isopropanol, compared with Au sites alone, thereby achieving ultrahigh acetone selectivity (99.3 %) over 1.1 wt % AuCu

Co3O4 is an important catalyst widely used for CO oxidation or electrochemical water oxidation near room temperature and was also recently used as support for single-atom catalysts (SACs). Co3O4 with a spinel structure hosts dual oxidation states of Co2+ and Co3+ in the lattice, leading to the complexity of its surface structure as the exposure of Co2+ and Co3+ has a significant impact on the performance of the catalysts. Although it is acknowledged that different facets exhibit varied catalytic activities and different abilities in hosting single atoms to provide active centers in SACs, the Co3O4 surface structure remains under-investigated. In this study, major facets of {111}, {110}, and {100} were studied down to subangstrom scale using advanced electron microscopy. We noticed that each facet has its own most stable surface configuration. The distribution of Co2+ and Co3+ on each facet was quantified, revealing a facet-dependent distribution of Co2+ and Co3+. Co3+ was found to be preferentially exposed on {100} and {110} as well as surface steps. Surface reconstruction was revealed, where a subangstrom scale shift of Co2+ was confirmed on facets of {111} and {100} due to polarity compensation and oxygen deficiency on the surface. This work not only improves our fundamental understanding of the Co3O4 surface structure but also may promote the design of Co3O4-based catalysts with tunable activity and stability.

MnO nanoparticles supported on coal-based activated carbon (AC) were facilely fabricated via incipient wetness impregnation method by calcination of manganese acetate in nitrogen. The as-prepared catalysts were characterized by N2 adsorption-desorption, XRD, TEM, and XPS. It is demonstrated that calcination under inert atmosphere can facilely obtain well dispersed MnO nanoparticles on AC, and the particle size, as well as the surface oxygen species of the catalysts strongly depended on the calcination temperature. The AC supported MnO nanoparticles all exhibited high catalytic activity toward ozone decomposition at room temperature, and an optimal one was displayed as the calcination temperature of 700 °C. The smallest particle size of MnO nanoparticles and the most amount of surface oxygen vacancies, were mainly responsible for the highest activity of MnO/AC-700. Moreover, lower loading of Mn was found to be more favorable for stable catalytic performance. This work reported a series of MnO based catalysts for efficient removal of ozone at room temperature for the first time, and may shed new lights on the design of manganese oxides with lower oxidation state for efficient ozone decomposition.

Volatile organic compounds (VOCs), methane, carbon monoxide, soot, automotive exhaust, and nitrogen oxides are harmful to the atmosphere and human health. It is urgent to strictly control their emissions. Heterogeneous catalysis is an effective pathway for the removal of these pollutants, and the critical issue is the development of novel and high-performance catalysts. In this review, we briefly summarize the preparation methods, physicochemical properties, catalytic activities, and related reaction mechanisms for the above pollutants removal of the rare earth oxides, mixed rare earth oxide, rare earth oxide-supported noble metal, and mixed rare earth oxide-supported noble metal catalysts that have been investigated by our group and other researchers. It was found that catalytic performance was associated with the factors, such as specific surface area, pore structure, particle size and dispersion, adsorbed oxygen species concentration, reducibility, reactant activation ability or interaction between metal nanoparticles and support. Furthermore, we also envision the development trend of such a topic in future work.

Volatile organic compounds (VOCs) and methane are pollutants that are harmful to the atmosphere and human health. It is highly required to control emissions of VOCs. Catalytic oxidation is one of the most effective pathways for the elimination of VOCs, in which the key issue is the development of novel and high-performance catalysts. In this review article, we briefly summarize the preparation strategies, physicochemical properties, catalytic activities, and stability for the oxidative removal of VOCs of the supported bimetallic catalysts that have been investigated by our group and other researchers. The supported bimetallic catalysts include the supported noble bimetal, supported noble metal-transition metal, and supported non-precious bimetal catalysts. It was found that catalytic performance was related to one or several factors, such as specific surface area, pore structure, particle size and dispersion, adsorbed oxygen species concentration, reducibility, lattice oxygen mobility, acidity, reactant activation ability, and/or interaction between bimetals or between metal and support. The stability and ability of anti-poisoning to water, carbon dioxide or chlorine were related to the nature of the bimetal and support in the catalysts. In addition, we also envision the development trend of such a topic in the future work.

Supported noble metal catalysts are highly effective for eliminating volatile organic compounds (VOCs). A catalyst with less noble metal loading is always desirable. Using a mixture of NaNO3 and NaF as molten salt, Fe(NO3)3 and Pt(NH3)4(NO3)2 as metal precursors, xPt/Fe2O3 catalysts (x = 0–0.3 wt%) were fabricated after calcination at 350 °C for 3 h. At space velocity of 40,000 mL/(g h), 0.22 wt% Pt/Fe2O3 showed the best catalytic activity, and o-xylene could be completely oxidized into CO2 and H2O at 225 °C. Furthermore, 0.22 wt% Pt/Fe2O3 exhibited good stability, and high resistance to water vapor, CO2, and SO2. We deduce that the excellent catalytic performance of 0.22 wt% Pt/Fe2O3 was associated with the high dispersion of the Pt species and good low-temperature reducibility. The possible reaction mechanism of o-xylene oxidation over 0.22 wt% Pt/Fe2O3 involved the adsorption of o-xylene molecules, partial decomposition into small organic intermediates (e.g. maleic anhydride and aliphatic carboxylate species), and total oxidation into CO2 and H2O. Due to the high efficiency, good stability, low cost, and convenient preparation, the present catalysts are promising for the practical removal of VOCs.

The strong interaction between Au nanoparticles and support (Au-metal oxide interface) usually governs the performance of a supported Au catalyst in heterogeneous catalysis. In this study, a series of Au/reduced graphene oxide (rGO)/three-dimensionally ordered macroporous (3DOM) Co