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Aerobic oxidative desulfurization (AODS) promises a sustainable alternative desulfurization process for fuel, yet is still limited by high temperature and low efficiency for oxygen activation. Here we report that the monolayer two-dimensional vanadium carbide (V2CTx) MXene can emerge as a robust and stable catalyst for the oxidation of thiophenic compounds with oxygen in air as an oxidant. The catalyst performs a higher mass specific activity over the state-of-art vanadium oxides, activates the reaction at 70 °C, and achieves effective conversion of various sulfides under mild condition. Coupling characterizations with DFT calculations, we reveal that the abundant low valence V species accompanied anion vacancies on the surface of MXene have excellent oxygen activation capacity, which well explains its outstanding catalytic performance at low temperature. Moreover, the catalyst maintains its activity after 6 cycles of reuse, and is expected to act as a sustainable, efficient and stable AODS catalyst. [ABSTRACT FROM AUTHOR]

Selective semi-hydrogenation of acetylene is an extremely important reaction from both industrial and theoretical perspectives. Palladium, due to its unique chemical and physical properties, is the most active and currently irreplaceable metal for this reaction in industry, but the poor catalytic selectivity towards ethylene is also its inherent shortcoming. Introducing a secondary metal to tune a geometric and electronic structures of Pd nanoparticles and to create a synergistic effect is the most widely used strategy to effectively improve the overall catalytic performance of Pd-based catalysts. Thus, various supported Pd-based bimetallic catalysts for selective semi-hydrogenation of acetylene have been exploited in the past decade. Timely comparison, analysis, and summarizing of various preparation methods may offer a beneficial reference for the subsequent development of such catalysts. In this context, herein, the advances in synthesis strategies of catalysts, including nano-catalysts, single atom alloys (SAAs), as well as bimetallic dual atom catalysts are summarized systematically. Their advantages and disadvantages are comparatively discussed. Finally, future perspectives for the synthetic strategies of supported Pd-based bimetallic catalysts for selective semi-hydrogenation of acetylene are proposed. [ABSTRACT FROM AUTHOR]

• Ni/CeO 2 is successfully prepared by plasma decomposition of nickel precursor. • The obtained Ni/CeO 2 catalyst shows a significantly high activity at low temperatures. • A up to 99.5 % methane selectivity was achieved. • In-situ XAS, XRD, and XPS characterizations were conducted. • Small Ni size, strong Ni-CeO 2 interaction and rich interfacial sites causes high activity. A Ni/CeO 2 catalyst was prepared via decomposition of nickel precursor by gas discharge plasma, followed by hydrogen reduction thermally. The activity of the obtained catalyst reaches the highest level towards CO 2 methanation with methane selectivity above 99 % at reaction temperatures lower than 300 °C. For example, the CH 4 formation rate at 275 °C is 100.3 μmol g cat −1 s−1, higher than the reported catalysts at the same reaction temperature. Characterization results indicate that the plasma decomposition leads to an interfacial structure where Ni atoms bind with O atoms from ceria. A strong metal-support interaction is caused. Rich interfacial Ni-CeO 2 sites are thus formed with excellent redox property. The unique interfacial structure confines small nickel particles on the ceria surface, exposing more metallic Ni as active sites for splitting H 2. Therefore, the plasma prepared Ni/CeO 2 catalyst shows balanced active sites for H 2 splitting and CO 2 activation, improving low temperature catalytic activity significantly. [ABSTRACT FROM AUTHOR]