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The RuO2@CemZr1−mO2−SiO2 catalysts were synthesized by the spontaneous deposition method. Based on the XRD patterns of various RuO2@CemZr1−mO2−SiO2 catalysts, it was suggested that the Ru noble metal nanoparticles were distributed with high dispersion on the surface of Ce‐modified porous matrix of ZrO2. H2‐TPR and NH3‐TPD confirmed that all catalysts possessed superior redox ability as well as acidity, which were facilitated to the catalytic dichloroethane (DCE) oxidation. From the systematic study of texture structure, surface properties and catalytic activity, we knew that acid sites were shown to be favorable for adsorption as well as activation of DCE and improve the anti‐poisoning property of the catalyst, and the redox ability could facilitate the further oxidation of the intermediate. The optimized RuO2@Ce0.1Zr0.9O2−SiO2 catalyst exhibited superior activity (T90=275 °C at a space velocity of 15000 h−1), good stability (at 300 °C for 50 h) and outstanding tolerance towards moisture (in 5 % moisture). Our work demonstrated the important role of acidity and redox ability over these functionalized catalysts, providing guidance for the advanced catalyst design. [ABSTRACT FROM AUTHOR]

The catalytic oxidation of volatile organic compounds (VOCs) is considered a feasible method for VOCs treatment by virtue of its low technical cost, high economic efficiency, and low additionally produced pollutants, which is of important social value. Single-atom catalysts (SACs) with 100% atom utilization and uniform active sites usually have high activity and high product selectivity, and promise a broad range of applications. Precise regulation of the microstructures of SACs by means of defect engineering, interface engineering, and electronic effects can further improve the catalytic performance of VOCs oxidation. In this review, we introduce the mechanisms of VOCs oxidation, and systematically summarize the recent research progress of SACs in catalytic VOCs total oxidation into CO2 and H2O, and then discuss the effects of various structural regulation strategies on the catalytic performance. Finally, we summarize the current problems yet to be solved and challenges currently faced in this field, and propose future design and research ideas for SACs in catalytic oxidation of VOCs. [ABSTRACT FROM AUTHOR]

Ceria (CeO2) has been regarded as one of the most promising industrial catalysts for hydrochloric acid (HCl) oxidation to replace RuO2‐based catalysts. Thermal sintering and chlorination of CeO2 limit its large‐scale application. In this work, ultrafine CeO2 nanodots embedded in a porous ZrO2 matrix (CeO2@ZrO2) are successfully prepared by a spontaneous deposition method and evaluated in HCl catalytic oxidation for sustainable Cl2 recycle. The physicochemical properties of CeO2@ZrO2 catalysts are characterized by means of XRD, Raman, SEM, TEM, BET, XPS, H2‐TPR and oxygen storage capacity (OSC). The results reveal that all CeO2@ZrO2 catalysts display large specific surface area, pore volume, perfect low‐temperature reduction performance and oxygen storage‐release capacity. More importantly, the unique structure of the CeO2 nanodots isolated by amorphous ZrO2 improves the dispersion and inhibits the sintering of active sites. The optimized 40CeO2@ZrO2 catalyst reveals superior activity (1.90 gCl2 ⋅ gcat−1 ⋅ h−1) and good durability (100 h under 430 °C). Kinetic studies reveal that the adsorption of O2 and HCl is competitive at the active sites, and the desorption of surface Cl is the rate‐determining step. [ABSTRACT FROM AUTHOR]

The CuO–CeO 2 composite oxides supported on Y-zeolite were prepared by means of wet-impregnation method. The derived catalysts exhibited excellent activities and high stabilities for gas-phase HCl catalytic oxidation to Cl 2 . 90% conversion of HCl can be accomplished at a reaction temperature as low as 390 °C. Comparing with the results reported in literature, the CuO(12)–CeO 2 (13)/Y catalyst developed in the current study showed exceptionally high space time yield for Cl 2 (62.7 mmol g cat − 1 h − 1 at 410 °C). A correlation between the characterization results and the activities of CuO–CeO 2 /Y suggested that higher content of well dispersed CuO species and intensive CuO–CeO 2 association (the formed Cu x Ce 1 − x O 2 − y and surface oxygen spillover) are critical to determine high activity. [ABSTRACT FROM AUTHOR]

• The active sites of α-MnO 2 are the Mn4+-O sur -Mn3+ structures on the surface. • The Langmuir-Hinshelwood mechanism with competitive adsorption plays a major role at low temperature. • There is synergism between Langmuir-Hinshelwood and Mars-van-Krevelen mechanisms at medium and high temperature. • A complete propane conversion path on MnO 2 surface is proposed. Mn-based oxides exhibit attractive catalytic activity for VOCs oxidation, but the catalytic mechanism and kinetics are still significant challenges and rarely mentioned. Therefore, we prepared OMS-2 manganese oxide octahedral molecular sieve with α-MnO 2 crystal phase as model compound. By analyzing the properties of the surface chemical states of the catalysts in different reaction stages, combined with the control experiments, the coordination of Mn4+-O sur -Mn3+ was confirmed as the active site at low temperature. Meanwhile, the reaction path of propane catalytic oxidation on MnO 2 surface based on condensation mechanism was proved by in-situ spectroscopy and density functional theory calculation. And kinetic studies revealed that the catalytic combustion of propane processed through Langmuir-Hinshelwood mechanism at low temperature. All these systematic study results supplied a well-defined understanding for the propane combustion over manganese oxide. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface reconstruction of Co 3 O 4 was created by plasma treatment technology. • The HCHO oxidation activity was significantly improved over the plasma-engraved Co 3 O 4 catalyst. • High surface area and rich oxygen vacancies are vital for enhanced activity. Improving the surface area and the number of oxygen vacancy are vital for superior catalytic oxidation performance. Here, plasma-engraved technique was used for surface modification of Co 3 O 4 nanostructure (cube and sphere morphology), which was applied to formaldehyde oxidation reaction. It was found that the formaldehyde oxidation can be boosted over plasma-engraved Co 3 O 4 nanostructure, and efficiently realized at room temperature. Based on varied characterizations, it revealed that the plasma-treatment endowed the Co 3 O 4 nanostructure with surface reconstruction (notches and broken fragments on surface), along with high surface area and rich oxygen vacancies. These factors contribute very important effort for improved activity. Besides, surface reaction mechanism was also proposed based on the in-situ DRIFTs, during which the CHOH was transformed to key intermediates (DOM, formate and/or carbonate), and finally to CO 2 and H 2 O. This study also provides a very efficient strategy for surface modification of heterogeneous solid catalyst and their expand application in environmental catalysis. [ABSTRACT FROM AUTHOR]