Anionic starch-induced Cu-based composite with flake-like mesostructure for gas-phase propanal efficient removal

Hierarchical Au/CeO2 systems – influence of Ln3+ dopants on the catalytic activity in the propane oxidation process

The catalytic activity of the hierarchical tube-like Au/Ce1−xLnxO2−x/2 in the propane oxidation process depends not only on the presence of Au nanoparticles on the support surface but also on the type of deformation in the CeO2 network.

Hierarchical macroparticles of ceria with tube-like shape – synthesis and properties

The hierarchical organization of CeO2 nanoparticles into tube-like macroparticles has a great influence on the properties of the material.

A Novel Porous Ceramic Membrane Supported Monolithic Cu-Doped Mn–Ce Catalysts for Benzene Combustion

Porous ceramic membranes (PCMs) are considered as an efficient hot gas filtration material in industrial systems. Functionalization of the PCMs with high-efficiency catalysts for the abatement of volatile organic compounds (VOCs) during dust elimination is a promising way to purify the industrial exhaust gases. In this work, we prepared PCMs (porosity: 70%) in a facile sintering process and integrated Cu-doped Mn–Ce oxides into the PCMs as monolithic catalysts by the sol–gel method for benzene oxidation. Through this method, the catalysts are dispersed evenly throughout the PCMs with excellent adhesion, and the catalytic PCMs provided more active sites for the reactant gases during the catalytic reaction process compared to the powder catalysts. The physicochemical properties of PCMs and catalytic PCMs were characterized systematically, and the catalytic activities were measured in total oxidation of benzene. As a result, all the prepared catalytic PCMs exhibited high catalytic activity for benzene oxidation. Significantly, the monolithic catalyst of Cu0.2Mn0.6Ce0.2/PCMs obtained the lowest temperature for benzene conversion efficiency of 90% (T90) at 212 °C with a high gaseous hourly space velocity of 5000 h−1 and showed strong resistance to high humidity (90 vol.%, 20 °C) with long-term stability in continuous benzene stream, which is caused by abundant active adsorbed oxygen, more surficial oxygen vacancy, and lower-temperature reducibility.

Removal of benzene by non-thermal plasma catalysis over manganese oxides through a facile synthesis method

Three manganese oxide catalysts (MnO_x) were synthesized via a simple method, and then they were introduced into the non-thermal plasma (NTP) system for benzene removal. The XRD and EXAFS results showed the MnO_x were mainly in the Mn₃O₄ phase, and from the analysis of N₂ adsorption/desorption isotherms, we knew the MnO_x calcined at 250 °C (Mn250) had the largest surface area of 274.5 m² g^-1. Besides, Mn250 also exerted higher benzene adsorption capacity (0.430 mmol g^-1) according to C₆H₆-TPD. O₂-TPD indicated that Mn250 showed better oxygen mobility than Mn300. Moreover, by analyzing XPS results, it revealed that Mn250 exhibited rich abundant of surface adsorbed oxygen species (O_ads) and moderate ratio of Mn⁴⁺/Mn³⁺, and the reducibility temperature was also the lowest among all the MnO_x catalysts drawn by H₂-TPR profiles. As a result, Mn250 combined with NTP could remove 96.9% of benzene at a low input power of 3 W (benzene concentration 200 ppm, and GHSV 60,000 mL g_cat.^-1 h^-1), performing the best catalytic activity among the three catalysts and plasma only. Furthermore, the "NTP + Mn250" system also produced the highest CO₂ concentration and lowest CO concentration in downstream, and the residual O₃ after catalytic reaction was also the lowest, that is to say, the synergistic effect between NTP and Mn250 was more effective than other catalysts in benzene removal. Graphical abstract.

Synergetic effect over flame-made manganese doped CuO–CeO2 nanocatalyst for enhanced CO oxidation performance

CuO–CeO₂ nanocatalysts with different amounts of Mn dopping (Mn/Cu molar ratios of 0.5 : 5, 1 : 5 and 1.5 : 5) were synthesized by flame spray pyrolysis (FSP) method and tested in the catalytic oxidation of CO. The physicochemical properties of the synthesised samples were characterized systematically, including using X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS), oxygen-temperature programmed desorption (O₂-TPD), hydrogen-temperature programmed reduction (H₂-TPR) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The results showed that the 1Mn–Cu–Ce sample (Mn/Cu molar ratio of 1 : 5) exhibited superior catalytic activity for CO oxidation, with the temperature of 90% CO oxidation at 131 °C at a high space velocity (SV = 60 000 mL g⁻¹ h⁻¹), which was 56 °C lower than that of the Cu–Ce sample. In addition, the 1Mn–Cu–Ce sample displays excellent stability with prolonged time on CO stream and the resistance to water vapor. The significantly enhanced activity was correlated with strong synergetic effect, leading to fine textual properties, abundant chemically adsorbed oxygen and high lattice oxygen mobility, which further induced more Cu⁺ species and less formation of carbon intermediates during the CO oxidation process detected by in situ DRIFTS analysis. This work will provide in-depth understanding of the synergetic effect on CO oxidation performances over Mn doped CuO–CeO₂ composite catalysts through FSP method.

The synergetic effect is promoted on Mn doped CuO–Ce O₂ catalyst to induce less carbon intermediates to enhance CO oxidation performance.

Efficient light-driven CO2 hydrogenation on Ru/CeO2 catalysts

An efficient catalysis system for light-driven CO₂ hydrogenation was designed and the function mechanism of light was investigated.

Transition metal based single chained surfactants: synthesis, aggregation behavior and enhanced photoluminescence properties of fluorescein

Four different transition metal based surfactants were synthesized. The effect of presence of metal as a part of counter ion on the aggregation behaviour of metallosurfactants and on the photophysical properties of fluorescein was explored.