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With the target to fabricate more feasible catalysts for SRM to produce hydrogen, the interaction between Ni and LaBO3 (B = Al, Cr and Fe) perovskite supports with different B-sites has been explored. To avoid the formation of big Ni grains, the Ni loading is intentionally set as low as 2 wt%. XRD and Raman results revealed that the three LaBO3 supports are composed of pure perovskite phase, but have differed fine crystal structures. While LaFeO3 and LaCrO3 can be indexed to the orthorhombic perovskite phase, LaAlO3 can be indexed to the hexagonal phase. H2-TPR and XPS results have validated that NiO has varied interfacial interactions with the LaBO3 supports through partial electron transfer from the supports to Ni. As a consequence, the active metallic Ni surface areas are in the order of 2%Ni/LaAlO3 > 2%Ni/LaCrO3 > 2%Ni/LaFeO3, well consistent with the reaction performance. Furthermore, by varying the B-site element, the abundance of the active surface oxygen species (mainly O22−) is varied, obeying the sequence of 2%Ni/LaCrO3 > 2%Ni/LaAlO3 > 2%Ni/LaFeO3, well consistent with the anti-coking ability of the catalysts. It is discovered that the change of the fine crystal structure of LaBO3 supports can influence the SRM performance of the 2%Ni/LaBO3 catalysts evidently. The reaction performance of the catalysts is mainly determined by the active Ni surface area, but the anti-coking ability is majorly decided by the amount of active oxygen species. [ABSTRACT FROM AUTHOR]

Achieving active and stable heterogeneous catalysts by encapsulating noble metal species within zeolites is highly promising for high utilization and cost efficiency in thermal and environmental catalytic reactions. Ru, considered an economical noble metal alternative with comparable performance, faces great challenges within MFI‐type microporous zeolites due to its high cohesive energy and mobility. Herein, an innovative strategy was explored that couples hydrothermal in situ ligand protection with stepwise calcination in a flowing atmosphere to embed ultrasmall Ru clusters anchored at K+‐healed silanol sites (≡Si−Ruδ+−O−K complexes) within 10‐membered ring sinusoidal channels of MFI. Comprehensive experiments and theoretical calculations unveiled that the interplay between confined Ru clusters and MFI induces local strain in MFI, creating a unique catalytic microenvironment around the Ru clusters. This synergy interaction enhances alkane deep oxidation as the confined Ru clusters and the MFI microenvironment collectively pre‐activate C3H8 and O2, facilitate the cleavage of C−H and C−C bonds at low temperatures. Notably, the stable geometric and electronic properties of the confined Ru show exceptional thermal stability up to 1000 °C, rivaling fresh catalysts. These findings shed vital methodological and mechanistic insights for developing efficacious heterogeneous catalysts for thermal catalysis. [ABSTRACT FROM AUTHOR]

Light alkanes make up a class of widespread volatile organic compounds (VOCs), bringing great environmental hazards and health concerns. However, the low-temperature catalytic destruction of light alkanes is still a great challenge to settle due to their high reaction inertness and weak polarity. Herein, a Co 3 O 4 sub-nanometer porous sheet (Co 3 O 4 -SPS) was fabricated and comprehensively compared with its bulk counterparts in the catalytic oxidation of C 3 H 8 . Results demonstrated that abundant low-coordinated Co atoms on the Co 3 O 4 -SPS surface boost the activation of adsorbed oxygen and enhance the catalytic activity. Moreover, Co 3 O 4 -SPS has better surface metal properties, which is beneficial to electron transfer between the catalyst surface and the reactant molecules, promoting the interaction between C 3 H 8 molecules and dissociated O atoms and facilitating the activation of C-H bonds. Due to these, Co 3 O 4 -SPS harvests a prominent performance for C 3 H 8 destruction, 100% of which decomposed at 165 °C (apparent activation energy of 49.4 kJ mol -1 ), much better than the bulk Co 3 O 4 (450 °C and 126.9 kJ mol -1 ) and typical noble metal catalysts. Moreover, Co 3 O 4 -SPS also has excellent thermal stability and water resistance. This study deepens the atomic-level insights into the catalytic capacity of Co 3 O 4 -SPS in light alkane purification and provides references for designing efficacious catalysts for thermocatalytic oxidation reactions., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)