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The Cr-doped CeO2–TiO2 catalysts (CrCeTi) were produced via a coprecipitation method and used for selective catalytic reduction (SCR). The CrCeTi catalyst has good catalytic performance and sulfur resistance. The results of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), NH3-TPD, NO-TPD, X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR) suggested that the CrCeTi catalyst with high specific surface area (SSA), strong surface acidity, enhanced redox properties, and effective electron transfer (3Ce4+ + Cr3+ ↔ 3Ce3+ + Cr6+) were the important promotion factors for excellent SCR properties. The in situ diffuse reflectance infrared spectroscopy (DRIFTS) indicated that the incorporation of Cr could improve the adsorption capacity of nitrate and the activation capacity of NH3, which were conducive to enhancing the catalytic activity. The thermogravimetric analysis-mass spectrometry (TG-MS) confirmed that the doping of Cr reduced SO2 surface adsorption and promoted the decomposition of NH4HSO4 (ABS). Therefore, the CrCeTi catalyst showed excellent resistance to SO2 poisoning.

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We report the application of partially reduced CuO nanoparticles as Cu-based catalysts for dimethyldichlorosilane (M2) synthesis via the Rochow reaction. The CuO nanoparticles (50–100 nm) were synthesized by a simple precipitation method and partially reduced in a H2/N2 mixture gas to obtain the Cu-based catalyst containing different Cu species of CuO, Cu2O, and Cu. It was found that the composition of the samples could be tailored by varying the volume ratio of H2/N2 at the given reduction temperature and time. Compared to the synthesized CuO and Cu nanoparticles, as well as the commercial CuO microparticles, these multicomponent Cu-based catalysts, particularly for the CuO–Cu2O–Cu catalyst, showed much higher M2 selectivity and Si conversion in the Rochow reaction. The enhanced catalytic performance is attributed to the smaller particle size and the synergistic effect among the different components. The work would help to develop novel ternary Cu-based catalysts for organosilane synthesis.

Manganese oxides are known to have good low-temperature SCR performance, whereas improving their medium-and high-temperature catalytic performance and N 2 selectivity remain a challenge. Herein, manganese-based ternary catalysts Fe− Mn/Ce, using CeO 2 as the carrier and Fe as the second active component, were constructed to effectively solve this problem. Fe−Mn/Ce catalysts show excellent catalytic performance, with NO x conversions of more than 90% over a wide operating temperature range (164.5−419.4 °C) with high and N 2 selectivity. Further investigation showed that, for the Fe−Mn/Ce catalyst with rich redox sites and surface acidity, higher amounts of Fe 2+ and Mn 4+ are the important factors promoting excellent SCR reactivity. Besides, the Fe modification can generate effective electron transfer to reduce the N 2 O generation pathway and increase the catalytic reaction sites, thus enhancing the overall catalytic performance.

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A series of CeO2 modified Cu‐SSZ‐13 monolith catalysts were prepared by embedding CeO2 into the washcoat of Cu‐SSZ‐13 monolith catalyst through solvent combustion method. These CexCu‐SSZ‐13 catalysts were studied in the selective catalytic reduction (SCR) of NO with NH3, among which the Ce2Cu‐SSZ‐13 catalyst exhibited the best low‐temperature activity, hydrothermal stability, and sulfur resistance. The physicochemical properties of the catalysts were characterized using multiple methods. Results showed that the acidity, redox capacity, and ammonia adsorption capacity significantly enhanced after CeO2 modification, thus leading to the high performance of Ce2Cu‐SSZ‐13 catalyst. Furthermore, the introduction of CeO2 induced the fast SCR reaction by promoting the oxidation of NO to NO2. Analog calculation suggested that the porous structure generated via solvent combustion in the washcoat effectively increased the diffusion rate of reaction. In situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFT) analysis showed that Brønsted acid sites were the main active center and the reaction followed Eley–Rideal mechanism.