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Mechanism of SO 2 effect on Cu 1-x Fe x CeZr catalysts for simultaneous removal of NO and toluene. [Display omitted] • The correlativity between the the reaction process and sulfur poisoning was studied. • The mechanism effect of SO 2 on the reaction process was studied. • A mechanism for simultaneous removal of NO and toluene was proposed. • The introduction of Fe enhanced oxygen vacancies formation and oxygen mobility. Developing non-vanadium-based SCR catalysts with high performances for simultaneous removal of NO and toluene at low-medium temperatures remains a challenge in addressing SO 2 poisoning. Herein, porous Fe-modified CuCeZr catalysts prepared via KIT-6 hard-templating method was conducted to investigate the simultaneous removal of NO and toluene at low-medium temperatures. A suite of experiments and characterizations was systematically used to probe into the effect of SO 2 on the reaction process. The results indicated that porous Fe-modified CuCeZr displayed excellent performance for simultaneous removal of NO and toluene. The introduction of Fe into CuCeZr enhances both acid sites and redox properties via the redox cycle between Cu2++Ce3+↔Cu++Ce4+ and Fe3++Ce3+↔Fe2++Ce4+ redox cycle. Importantly, Fe incorporation leads to the formation of lattice defects and oxygen vacancies, generating abundant active sites that mitigate the detrimental effects of SO 2 poisoning, and promote the efficient removal of NO and toluene simultaneously. Besides, a mechanism influence of SO 2 on the reaction process for simultaneous removal of NO and toluene at low-medium temperatures was proposed. This mechanism has the potential to provide an effective solution for developing non-vanadium-based SCR catalysts with sulfur resistance. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The MoP/CN samples exhibit superior activity in CO 2 reduction and H 2 evolution. • The CO 2 adsorption and conversion progress is well revealed in the photoreaction. • The efficient co-catalyst MoP facilitates the separation and transfer of charges. Abstract Photoreduction CO 2 to hydrocarbons and photosplitting water for H 2 production are the most promising, sustainable approaches for environmental pollution alleviation and solar-to-chemical energy conversion. However, developing low-cost, high efficient and stable photocatalysts remains a great challenge. Herein, we reported a novel visible-light activated MoP co-catalyst loaded g-C 3 N 4 photocatalyst for CO 2 reduction and water splitting under simulated irradiation firstly. Experimental results demonstrated that the composites were highly active and exhibited superior stability. The maximum CO and H 2 evolution rates of 0.92 μmol h−1 and 40.38 μmol h−1 were achieved on MoP/CN-15% catalyst, which were 4.5-fold and 74.5-fold higher than the pure g-C 3 N 4 , and the corresponding apparent quantum efficiencies (AQE) were 3.5% and 18.3% at 420 nm, respectively. In situ FTIR analysis disclosed the CO 2 adsorption and conversion progress, in which the COO− acted as a major intermediate. Furthermore, comprehensive characterization analysis revealed the introduction of MoP facilitated the separation and transfer of photogenerated electron-hole pairs, and the theoretical calculation by density functional theory (DFT) also confirmed that MoP could effectively separate the photoexcited charges from g-C 3 N 4. Combining with experimental and DFT calculations results, a new way to design cost-effective photocatalysts has been enlightened. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fe 3 O 4 @PS-TMG was synthesized by immobilizing TMG onto the shell of nanohybrids. • The loading of TMG as well as surface property of catalyst can be well regulated. • The MPIC can stabilize soybean oil-in-methanol Pickering emulsion. • The MPIC exhibited higher catalytic activity for transesterification. Abstract A novel magnetic Pickering interfacial catalyst (MPIC) was developed and used for highly effective and clean production of biodiesel. The catalyst was synthesized by immobilization of 1,1,3,3-tetramethylguanidine (TMG) onto the shell of Fe 3 O 4 @Chloromethyl PS nanohybrids. The resultant Fe 3 O 4 @PS-TMG was measured by transmission electron microscope (TEM), dynamic lighting scattering (DLS), Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA), thermogravimetric analysis (TG), contact angles (CA). The results showed that surface property and TMG loading of catalyst can be finely regulated via adjusting the feeding of TMG. Fe 3 O 4 @PS-TMG with amphiphilic surface can stabilize soybean oil-in-methanol Pickering emulsion, which would offer large interfacial area and surface enrichment of reactants, leading to a significant enhancement of such liquid-liquid (L-L) biphasic reaction with high mass transfer resistance. Furthermore, the MPIC can be facile separated from the mixture of reaction by magnet, and showed excellent stability over 5 recycles. [ABSTRACT FROM AUTHOR]

We report herein the design and preparation of novel magneto-polymeric nanohybrids that can be used as efficient and recyclable Pickering interfacial catalyst (PIC) in selective oxidation of alcohols. The nanohybrids Fe 3 O 4 @SiO 2 @PTMA, bearing catalytic TEMPO functionalities, were synthesized through distillation-precipitation polymerization (DPP) of the precursor monomer 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TMPM) and subsequent oxidation reaction. TEM, FT-IR, DLS, EA confirmed and quantified the TEMPO loading of nanohydrids (1.0–2.4 mmol · g −1 ). It was found that the TEMPO loading, particle size, as well as surface hydrophilicity could be finely tuned via simply adjusting the TMPM monomer fraction during polymerization. The performance of the resultant nanohybrids as PIC was then evaluated in a typical Anelli system, which showed superior catalytic activity for selective oxidation of alcohols. Moreover, the PIC can be easily recycled by applying magnetic field, and reused for the following cycles of oxidation without any loss on either conversion or selectivity. [ABSTRACT FROM AUTHOR]

Abstract: Three-component reactions of aldehydes, amines and diethyl phosphite are efficiently catalyzed by ytterbium perfluorooctanoate [Yb(PFO)3] under solvent-free conditions, giving the corresponding α-aminophosphonates in good to excellent yields. The catalyst can be recovered and reused for several times without any significant loss of activity. Furthermore, a possible mechanism for this transformation is also presented. [Copyright &y& Elsevier]

[Display omitted] As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C 3 N 4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn 2 S 4 (ZIS). A ternary NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H 2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 (NiS/ZIS/UCN) achieved a H 2 evolution yield reached to 5.02 mmolg−1h−1, which was 5.23 times superior than that of pristine ZnIn 2 S 4 (0.96 mmolg−1h−1) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn 2 S 4 (4.08 mmolg−1h−1). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H 2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H 2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion. [ABSTRACT FROM AUTHOR]

The microwave pyrolysis system was used to study the effects of mixed additives on the microwave pyrolysis of Dunaliella salina. The mixed additive is a mixture of SiC and Na2CO3. The different weights of addition (5%, 10%, and 20%) of mixed additives, different mixing ratios (SiC:Na2CO3 = 0:10, 3:7, 5:5, and 6:4), and different kinds of additives (single additive and mixed additive) were studied. According to the findings, when the catalyst was 5% Na2CO3, the total weight loss (Mt) was maximum. The minimum Mt occurred at the 5% SiC group; when the mixed additive weight of addition was 10% and the mixing ratio of SiC:Na2CO3 = 5:5, the average weight loss rate (Rv) and weight loss rate for the first peak (Rp1) were maximum, and the time corresponding to the first peak (tp1) was minimum. Besides, SiC and Na2CO3 had a cooperative action when the mixed additive weight of addition was 10% and the mixing ratio of SiC:Na2CO3 = 5:5. For the total electricity consumption in microwave pyrolysis and oil and gas production per unit of electricity consumption, the mixed additive group with the weight of addition was 10% and the mixing ratio of SiC:Na2CO3 = 5:5 was better. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the cascade reaction of o-aminoacetophenone with methanamine using Sc(OTf)3 as catalyst.

[Display omitted] • Solvent-redox hydrothermal process was employed to constructure MnO x –D oxides. • MnO x –D catalyst exhibites superior catalytic activity for aerobic oxidation of biomass–derived R–CH 2 –OH. • Adsorbed H 2 O on MnO x –D catalyst was found to enhance its superior catalytic activity. Manganese oxides (MnO x) have been emerged as highly active catalysts for the aerobic oxidation of biomass-derived compounds. Herein, a facile urea–redox hydrothermal method was employed to scalable synthesis of MnO x oxides with surface abundant unsaturated Mn and O species. The defective MnO x (MnO x –D) catalyst exhibits remarkable catalytic performance, enabling the room-temperature aerobic oxidation of biomass–derived alcohols with yields exceeding 99%. This represents a substantial 90.8-fold increase in activity compared to commercial MnO 2. Moreover, MnO x –D catalyst demonstrates broad substrate scopes for various biomass–derived alcohols and displays recyclability for the aerobic oxidative conversion of 5-hydroxymethylfurfural (HMF) over five cycles. Through a comprehensive analysis involving X–ray photoelectron spectroscopy (XPS), in–situ infrared (IR) spectroscopy, and controlled experiments, it is established that the presence of surface–adsorbed H 2 O species on MnO x –D catalyst significantly influences its catalytic performance. Mechanism studies reveal that the aerobic oxidation of biomass–derived R–CH 2 –OH compounds into the corresponding aldehydes can proceed via radical and non–radical pathways. Notably, the catalytic activity of MnO x –D catalyst in both pathways is mediated by the surface adsorbed H 2 O species. In the radical route, surface adsorbed H 2 O and O 2 species are converted into active •OH radical species, while in the non–radical route, surface adsorbed H 2 O can form a complex of HMF––H 2 O species. Both processes enhance the abstraction of H from the O–H and C–H bonds in the R–CH 2 –OH compounds on MnO x –D catalyst. This discovery could potentially guide the development of efficient metal oxidic catalysts for the oxidation of biomass–derived R–CH 2 –OH compounds. [ABSTRACT FROM AUTHOR]

Atom transfer radical polymerization (ATRP) has been considered to be an efficient strategy for constructing functional macromolecules owing to its simple operation and versatile monomers, and thus it is of great significance to develop ideal catalysts with higher activity and perfect reusability. We constructed a peroxidase mimic through the grafting of heme onto metal-organic frameworks UiO-66-NH 2 (ZrMOF), namely Heme-ZrMOF. After the systematic characterization of structure, the composite Heme-ZrMOF was demonstrated to possess high peroxidase activity using 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) and 3,3′,5,5′-tetramethylbenzidine as substrates. The enzyme mimic was then used as catalysts in the ATRP reactions of different monomers, in which favorable monomer conversion (44.6–98.0%) and product molecular weight (8600–25,600 g/mol) could be obtained. Compared to free heme, Heme-ZrMOF could efficiently achieve the easy separation of heme from the catalytic system and facilitate the ATRP reaction in an aqueous environment to avoid the utilization of organic solvents. In conclusion, the enzyme mimic Heme-ZrMOF could be potentially used as an effective catalyst for preparing well-defined polymers with biomedical applications. [ABSTRACT FROM AUTHOR]

Mechanism of SO 2 effect on mesoporous CuFeAlZrO x catalyst for simultaneous removal of Hg0 and NO. [Display omitted] • Amorphous CuFeAlZrO x catalysts with mesoporous structure were synthesized via a simple co-precipitation method. • The Cu 1 FeAlZrO x exhibited high catalytic activity and good SO 2 resistance at 275–390 ℃. • The synergistic effect of Cu and Fe tune the redox and acidity property with appropriate balance. • A possible mechanism for SO 2 effect on simultaneous removal of NO and Hg0 at wide temperature was proposed. Mesoporous CuFeAlZrO x catalyst is a promising substitute of V-based catalysts for potential candidate for simultaneous removal of Hg0 and NO due to its excellent performance at a broad temperature range. SO 2 poisoning effects remain a challenge in development of efficient SCR catalysts for applications. In this paper, the effect of SO 2 on mesoporous CuFeAlZrO x catalyst for simultaneous removal of Hg0 and NO at wide temperature range was studied. Relevant characterization techniques of H 2 -TPR, NH 3 -TPD, TG, SO 2 -TPD, XPS, Hg-TPD and in situ DRIFTS were used to reveal the correlativity between the physicochemical properties and SO 2 resistance of CuFeAlZrO x catalysts. SO 2 exhibited an inhibitory effect at low temperature (<300 °C) but a facilitative effect at high temperature(≥300 °C) for NH 3 -SCR reaction. At the same time, a promoting effect on Hg0 removal was observed during the whole temperature range. The deposition of NH 4 HSO 4 and the decrease of redox capacity caused the loss of SCR activity at low temperatures, while the formed iron sulfate provided more Lewis acid sites facilitate the high-temperature SCR performance due to the strong electron withdrawing effect of the S O double bonds. In addition, the generation of iron sulfates and NH 4 HSO 4 on mesoporous Cu 1 FeAlZrO x were alleviated because of the sacrifice of copper sites and promoted NH 4 HSO 4 decomposition in mesopore channels. SO 2 reacted with Hg0 to form HgSO 4 and Hg 2 SO 4 , which contributed to Hg0 removal performance. [ABSTRACT FROM AUTHOR]

Carbon-incorporated Co3O4 nanoparticles with an average diameter of 50 nm were prepared via a facile and environmentally friendly one-pot carbon-assisted method using degreasing cotton as a template as well as a reactant. The elemental analysis indicates the incorporation of carbon species into the Co3O4 nanoparticles and the XPS measurements demonstrate the presence of carbon species which comes from the incomplete combustion of the degreasing cotton. Interestingly, the resultant sample was able to split pure water into hydrogen under visible light irradiation without any cocatalyst, which is mainly due to the enhanced light absorption behavior confirmed by the UV-Vis absorption spectra. This facile method provided a potential strategy for applying narrow bandgap semiconductors in pure water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • A possible mechanism for the simultaneous oxidation of NO and toluene was proposed. • A-site partial substitution with Co can tune the structural properties of La 1-x Co x FeO 3. • The poisoning effects of H 2 O on the performance was studied. • The Interplay between toluene oxidation and NO oxidation were explored. To provide insight into optimizing flue gas treatment, the reaction mechanism for simultaneous oxidation of NO and toluene with H 2 O using a A-site substituted La 1-x Co x FeO 3 (x = 0–0.4) catalysts with three-dimensional porous structure was investigated. The results demonstrated that the partial substitution of La in porous LaFeO 3 by Co can induce the structural distortion, promote the specific surface area, enhance more active site exposure and produce abundant reactive oxygen species, including lattice oxygen with higher mobility, more surface adsorbed oxygen as well as oxygen vacancies, which improved the catalytic activities remarkably. Besides, NO and toluene have mutual promoted effects in the reaction system. The inhibition effect of H 2 O on simultaneous oxidation of NO and toluene was confirmed in that H 2 O consumes the chemisorbed active oxygen atoms. Without H 2 O, absorbed NO reacts with chemisorbed oxygen to form NO 2 , and absorbed toluene is oxidized by lattice oxygen to generate intermediate species which finally completely oxidized into CO 2 and H 2 O. With H 2 O, H 2 O react with chemisorbed oxygen to produce OH species that occupied active sites for toluene adsorption. NO interacts with OH species to form stable nitrate species, which offsets the inhibitive effect of H 2 O on NO oxidation due to the consumption of chemisorbed oxygen. [ABSTRACT FROM AUTHOR]

Abstract: One-pot three-component synthesis of 1,8-dioxo-9,10-diaryl-decahydroacridines in water was efficiently realized in the presence of the Brønsted acidic imidazolium salts containing perfluoroalkyl tails in good yields. The method provided several advantages such as low catalyst loading; recycle of the catalyst and simple work procedure. [Copyright &y& Elsevier]

Deuterohemin-β-Ala-His-Thr-Val-Glu-Lys (DhHP-6), a novel Deuterohemin-containing peptide mimetic of natural microperoxidase-11 (MP-11), was successfully immobilized onto NH 2 -UIO-66 (ZrMOF) by precipitation and cross-linking strategy to obtain a peroxidase mimetic, DhHP-6- c -ZrMOF. The synergy between components offers DhHP-6- c -ZrMOF excellent kinetics performance, peroxidase activity, pH stability, and phenol degradation capacity. Up to 98.0% of phenol could be degraded in 120 min when utilizing DhHP-6- c -ZrMOF as heterogeneous Fenton catalyst. Notably, DhHP-6- c -ZrMOF delivered outstanding recoverability with an 80.2% degradation ratio of phenol after four recycles. The efficient peroxidase mimetic can potentially be used as a promising catalyst for the high-efficiency degradation of phenol pollutants. Unlabelled Image • Precipitation and cross-linking strategy for construction of peroxidase mimetic (DhHP-6- c -ZrMOF). • Characterization of the immobilization of DhHP-6 onto ZrMOF. • DhHP-6- c -ZrMOF delivered enhanced kinetics performance, peroxidase activity, pH stability. • Synergistic mechanism offers the material excellent phenol degradation capacity and recoverability. [ABSTRACT FROM AUTHOR]