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• Microkinetic analysis is used to screen perovskites for methane partial oxidation. • The catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3. • Bulk oxygen vacancy formation energy is identified as a single descriptor. • 667 combinations of A- and B-cations have been screened in terms of stability. • SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are identified as catalyst candidates. DFT calculations and descriptor-based microkinetic analysis have been performed to screen ABO 3 perovskite catalysts for methane partial oxidation. The scaling relations indicate the adsorption energies of H@O and CH 3 @B have the capability of representing the energetics of methane oxidation, and bulk oxygen vacancy formation energy is identified to be a better single descriptor of the kinetics. The resultant volcano-shaped plot shows the catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3 , which agrees with the experimental findings and thus validates our theoretical predications. By screening 667 combinations of A- and B-cations based on electron neutrality, structural tolerance factors, and experimental verification, 77 ABO 3 have been identified to be stable. Of them, SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are located at the summit of the volcano, which also exhibit satisfactory CO selectivity and enhanced carbon resistance compared to LaFeO 3 , and may act as the oxygen carrier candidates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both size and support effects of Au catalysts are explored for MAL conversion. • The Au edge site is identified as the main active site for MMA generation. • A kinetics strategy for disentangling Au geometric and electronic effects is presented. The direct oxidative esterification of methacrolein (MAL) has drawn considerable attention as a promising route to produce methyl methacrylate (MMA). Here, we report a kinetics strategy to identify the active sites of Au catalyst for its disentanglement of geometric and electronic effects on this reaction. A series of Al 2 O 3 and CeO 2 supported Au catalysts are prepared by urea deposition–precipitation method, whose particle sizes are tailored by changing the vacuum-drying temperature. Their catalytic activity is correlated with Au particle size based on a crystal structure modelling, in which the Au edge site is identified as the main active site. The reduction in the valence electron population of Au 5 d states facilitates the adsorption of MAL, thus the positive core-level shift of Au 4f levels for each support gives rise to a higher production of MMA. This kinetics strategy could be extended to the design of other metal catalysts for this reaction. [ABSTRACT FROM AUTHOR]

The activated carbon treated at different temperatures was performed as a catalyst for the oxidation of glycerol to glycolic acid. Heat treatment at suitable temperature could promote the enrichment of ester and carboxyl functional groups with strong electronegativity, which serves as the efficient active site for the glycerol oxidation. Therefore, the optimal AC-400 catalyst with more ester and carboxyl groups shows excellent catalytic activity (0.0039 mol/g Cat /h) and GLYOA selectivity (53.2%). [Display omitted] • The efficient oxidation of glycerol to glycolic acid was realized over heat treated activated carbon. • Heat treatment tuned the composition and electronic structure of oxygen-containing functional groups. • The ester and carboxyl functional groups with strong electronegativity enhanced the adsorption and activation of glycerol. Exploring efficient and cheap catalyst for the selective oxidation of glycerol to valuable carboxylic acids is a critical and complicated challenge. Herein, we innovatively realized the efficient oxidation of glycerol to glycolic acid over metal-free catalyst under mild conditions via carbon material defect engineering. Multiple characterizations revealed that the stepwise functionalization of active carbon caused by simple high temperature control is adopted to fine-tune the composition and electronic structure of oxygen-containing functional groups. Specifically, the abundant ester and carboxyl functional groups exhibit stronger electronegativity than the hydroxyl group, and this enhanced electronic coupling effect strengthens the adsorption of glycerol, thus improving the catalytic activity. Kinetic analysis and density functional theory calculations demonstrated that the oxygen-containing functional groups (mainly ester and carboxyl) could promote the C–H bond activation of RCH 2 O* intermediate and once C–C bond cleavage of glyceric acid, ensuring the high selectivity of glycolic acid (53.2% over AC-400 catalyst). We anticipate that this work could sheds some light on the application and design of more new type of carbon-based metal-free catalysts in the aqueous phase oxidation of various polyols. [ABSTRACT FROM AUTHOR]