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Due to the capacity to offer abundant catalytic sites within porous solids featuring high surface areas, metal-organic frameworks (MOFs) and their derivatives have garnered considerable attention as prospective catalysts in environmental catalysis. To promote the industrial application of MOFs, there is an urgent need for an effective and environmental-friendly preparation approach. Breaking through the limitation of the traditional two-step preparation method that Pd was introduced to the already prepared Ce-BTC (Pd/Ce-BTC, BTC = 1, 3, 5 benzenetricarboxylate), in this work, we present a novel one-pot solvothermal method for synthesizing the Pd material supported by Ce-BTC (Pd@Ce-BTC). After pyrolysis in N 2 flow or air flow, Pd-CeO 2 catalysts derived from Pd@Ce-BTC exhibited much higher CO oxidation activity than those from Pd/Ce-BTC. Moreover, Pd/Ce-BTC and Pd@Ce-BTC pyrolyzed in N 2 flow (Pd/Ce-BTC-N and Pd@Ce-BTC-N) could better catalyze the oxidation of CO than Pd/Ce-BTC and Pd@Ce-BTC pyrolyzed in air flow (Pd/Ce-BTC-A and Pd@Ce-BTC-A). Further characterizations revealed that the abundant surface Ce3+ species, rich surface adsorbed oxygen species and superior redox properties were the main reasons for the superior CO oxidation activity of Pd@Ce-BTC-N. [Display omitted] • A one-pot solvothermal method was developed for the preparation of Pd incorporated in Ce-BTC • The Pd-CeO 2 catalyst derived from one-pot generated Pd@Ce-BTC exhibited superior CO oxidation activity • The activity of the Pd-CeO 2 catalyst obtained through pyrolysis in nitrogen flow surpassed that obtained in air flow • High Pd dispersion and rich surface Ce3+ species contributed to the improved CO oxidation activity on Pd-CeO 2 [ABSTRACT FROM AUTHOR]

A novel CeO 2 /TiO 2 -MoO 3 (Ce/TM) catalyst was synthesized by using of Mo as a bulk dopant to boost the NH 3 -SCR performance of CeO 2 /TiO 2 catalyst. It displayed 100% NO conversion at 200–350 °C under 60,000 mlg −1  h −1 and high tolerance to H 2 O and SO 2 at 250 °C. Characterization results manifested that the doping of Mo not only resulted in more Brønsted acid and Lewis acid sites formed on the Ce/TM surface, but also increased the specific surface area and redox ability of the catalyst, all of which account for the enhanced NH 3 -SCR activity. [ABSTRACT FROM AUTHOR]

• The competitive adsorption between SO 2 and NO x is the main reason for the decrease of activity in low temperature. • The formation and consumption of ABS reach a dynamic equilibrium, making the negative effect on the SCR activity limited. • The accumulation of ferric sulfate species enhances the surface acidity and promotes E-R pathway, further facilitating the activity. • The higher the temperature, the more SO 4 2− accumulated, and the rapider climbing rate of the catalytic activity. SO 2 poisoning of NH 3 -SCR catalysts at low temperature (< 300 °C) is still an austere challenge. In this work, γ-Fe 2 O 3 was taken as a model catalyst and the effect of reaction temperature on the catalytic activity in the presence of SO 2 were fully revealed. SO 2 introduction has no negative effect on the activity at 300 °C, which gradually improves with the extension of time. While for 225−275 °C, the activity decreases firstly and then increases slowly. The formatted sulfate species inhibits the adsorption of NO x , cuts off L-H reaction pathway and leads to the initial decline. While the deposited ammonium bisulfate (ABS) can be consumed continuously by NO + O 2 , implying the formation and consumption of ABS have reached a dynamic equilibrium. Moreover, the formation of ferric sulfate species results in the enhancement of surface acidity, which leads to the promotion of the E-R reaction pathway and further facilitates the increase of activity. [ABSTRACT FROM AUTHOR]