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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]

Understanding the nature of active sites on metal oxide catalysts in the selective catalytic reduction (SCR) of NO by NH 3 (NH 3 -SCR) is a crucial prerequisite for the development of novel efficient NH 3 -SCR catalysts. In this work, two CeO 2 -based SCR catalyst systems with diverse acidic metal oxides-CeO 2 interfaces, i.e., Nb 2 O 5 -CeO 2 (Nb 2 O 5 /CeO 2 and CeO 2 /Nb 2 O 5) and WO 3 -CeO 2 (WO 3 /CeO 2 and CeO 2 /WO 3), were prepared and used to reveal the relationship between NH 3 -SCR activity and surface acidity/redox properties. In combination with the results of the NH 3 -SCR activity test and various characterizations, it was found that the NH 3 -SCR performance of Nb 2 O 5 -CeO 2 and WO 3 -CeO 2 catalysts was highly dependent on the strong interactions between the redox component (CeO 2) and acidic component (Nb 2 O 5 or WO 3), as well as the amount of paired redox-acid sites. From a quantitative perspective, an activity-surface acidity/redox property relationship was proposed. For both Nb 2 O 5 -CeO 2 and WO 3 -CeO 2 catalysts systems operated at the more concerned low-temperature range (200 °C), the NH 3 -SCR activity in low NO x conversion region (< 40%) was mainly dominated by the surface acidity of catalysts, while the NH 3 -SCR activity in high NO x conversion region (> 40%) was more determined by redox properties. [Display omitted] • Nb 2 O 5 -CeO 2 and WO 3 -CeO 2 catalysts with tuned redox-acid property were synthesized. • Paired redox-acid sites formed through strong interaction between Nb 2 O 5 /WO 3 and CeO 2. • NH 3 -SCR activity was well controlled by the paired redox-acid sites. • Surface acidity and redox property were investigated from a quantitative perspective. • A clear surface acidity/redox property-activity relationship was established. [ABSTRACT FROM AUTHOR]