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Catalytic diesel soot combustion was examined using a series of Mn2O3 catalysts with different morphologies, including plate, prism, hollow spheres and powders. The plate‐shaped Mn2O3 (Mn2O3‐plate) exhibited superior carbon soot combustion activity compared to the prism‐shaped, hollow‐structured and powdery Mn2O3 under both tight and loose contact modes at soot combustion temperatures (T50) of 327 °C and 457 °C, respectively. Comprehensive characterization studies using scanning electron microscopy, scanning transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, temperature‐programmed reduction and oxygen release measurements, revealed that the improved activity of Mn2O3‐plate was mainly attributed to the high oxygen release rate of surface‐adsorbed active oxygen species, which originated from oxygen vacancy sites introduced during the catalyst preparation, rather than specific surface‐exposed planes. The study provides new insights for the design and synthesis of efficient oxidation catalysts for carbon soot combustion as well as for other oxidation reactions of harmful hydrocarbon compounds. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) has been regarded as a favorable photocatalytic co‐catalyst and efficient hydrogen evolution reaction (HER) electrocatalyst alternative to expensive noble‐metals catalysts, owing to earth‐abundance, proper band gap, high surface area, and fast electron transfer ability. In order to achieve a higher catalytic efficiency, defects strategies such as phase engineering and vacancy introduction are considered as promising methods for natural 2H‐MoS2 to increase its active sites and promote electron transfer rate. In this study, we report a new two‐step defect engineering process to generate vacancies‐rich hybrid‐phase MoS2 and to introduce Ru particles at the same time, which includes hydrothermal reaction and a subsequent hydrogen reduction. Compositional and structural properties of the synthesized defects‐rich MoS2 are investigated by XRD, XPS, XAFS and Raman measurements, and the electrochemical hydrogen evolution reaction performance, as well as photocatalytic hydrogen evolution performance in the ammonia borane dehydrogenation are evaluated. Both catalytic activities are boosted with the increase of defects concentrations in MoS2, which ascertains that the defects engineering is a promising route to promote catalytic performance of MoS2. Having major defects: Defect engineering of MoS2 to improve electrocatalytic/photocatalytic performances for hydrogen production was examined. [ABSTRACT FROM AUTHOR]

Pd nanoparticles (NPs) supported on Ti-doped graphitic carbon nitride (g-C3N4) were synthesized by a deposition-precipitation route and a subsequent reduction with NaBH4. The features of the NPs were studied by XRD, TEM, FTIR, XPS, EXAFS and N2-physisorption measurements. It was found that the NPs had an average size of 2.9 nm and presented a high dispersion on the surface of Ti-doped g-C3N4. Compared to Pd loaded on pristine g-C3N4, the Pd NPs supported on Ti-doped g-C3N4 exhibited a high catalytic activity in formic acid dehydrogenation in water at room temperature. The enhanced activity could be attributed to the small Pd NPs size, as well as the strong interaction between Pd NPs and Ti-doped g-C3N4. [ABSTRACT FROM AUTHOR]