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• Constructing more interfacial Auδ--O V -Zr3+ active sites by tuning the crystal structure of ZrO 2 supports. • Interfacial Auδ--O V -Zr3+ structure exhibits strong electrons transfer from tetragonal-ZrO 2 to Au atom. • The O V -Zr3+ could facilitate the adsorption of methacrolein substrate. • The electron-rich Auδ- species could promote the C H bond activation of the negatively charged intermediate. Constructing abundant metal-support interfacial active sites is an effective strategy to boost catalytic performance toward interfacial electronic structure-sensitive reactions, such as oxidative esterification of oxygenates. Herein, we successfully promote the generation of the interfacial active sites via tuning the crystal phases of Au/ZrO 2 catalysts. Multi-characterizations (such as in-situ FT-IR spectra and reaction kinetics) and density functional theory (DFT) calculations demonstrated that the interfacial Auδ--O V -Zr3+ structure with the synergistic effect exhibits strong electrons transfer from tetragonal-ZrO 2 to Au atom. Specifically, the O V -Zr3+ could facilitate the adsorption of methacrolein substrate, and the electron-rich Auδ- species could promote the C H bond activation of the CH 2 C(CH 3)CHOOCH 3 intermediate. Therefore, the interface-rich Au/t-ZrO 2 catalyst achieved nearly 90 % yield of MMA and excellent catalyst stability without the incorporation of second promoter. The outcome of this work could provide some insights into developing an efficient Au-based catalyst in the oxidative esterification system. [ABSTRACT FROM AUTHOR]

Based on density functional theory (DFT) calculation and microkinetic analysis, metal single-atom-doped ZSM-5 zeolite catalysts for naphtha cracking are screened. The calculation results show that the strong electronic interaction between metal single atom and zeolite skeleton (especially Ag and Cu) could enhance structural stability. The volcanic diagram of turnover frequency shows that Ag and Cu doped ZSM-5 zeolite catalyst is at the top of the volcano, which is close to the best choice. [Display omitted] • Metal single-atom-doped ZSM-5 zeolite catalyst exhibits good structural stability. • The adsorption of naphtha hydrocarbon molecules and the activation of C–H bond are greatly promoted. • The binding energy of carbon and hydrogen can be used as a descriptor for the catalytic cracking of naphtha on M−ZSM−5. • Ag and Cu single-atom-doped ZSM-5 are predicted to exhibit excellent catalytic activity. • Mo and Pd single-atom-doped ZSM-5 display great potential in the enhancement of propylene selectivity. Metal doped ZSM-5 catalyst has attracted much attention due to its unique catalytic activity for C–H bond activation. In this work, based on density functional theory (DFT) calculations and microkinetic analysis, we prospectively explored the catalytic activity of 12 kinds of transition metals (M = Fe, Co, Ni, Cu, Mo, Ru, Rh, Pd, Ag, W, Pt, Au) single-atom-doped ZSM-5 zeolite catalysts in the catalytic cracking of naphtha. The results show that there is a strong electronic interaction between metal atom and ZSM-5 skeleton. This induced stable structure could improve the adsorption ability of hydrocarbon, thus promoting the activation of C–H bond and the cracking of carbenium ion. Moreover, C and H binding energy were identified as descriptors in describing catalytic activity via good scaling relations. The turnover frequency volcano diagram shows that the Ag and Cu doped ZSM-5 zeolite catalyst is close to the best choice. In addition, Pd and Mo are potential metal choices with good selectivity through selectivity analysis. This work has important guiding significance for understanding the fluid catalytic cracking (FCC) mechanism and designing high-efficiency cracking catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe and K were introduced into Pt/MOR catalysts to modulate the reactants adsorption in CO-PROX. • 1Pt0.1 K/Fe-MOR achieves 100% CO conversion and 60–70% CO 2 selectivity within 130–200 °C. • Fe improves the CO conversion by providing more oxygen vacancies to activate O 2. • K promotes the CO 2 selectivity by enhancing CO adsorption and weakening H 2 adsorption on Pt. Developing efficient and stable catalysts for preferential oxidation of CO (CO-PROX) within a wide temperature window is significant for the industrial hydrogen resource purification process. Herein, dual promoters of Fe and K were deliberately introduced to the mordenite supported Pt catalyst for optimizing the adsorption behaviors of reactants in CO-PROX. The optimal 1Pt0.1 K/Fe-MOR catalyst can achieve 100% CO conversion and 60–70% CO 2 selectivity (the ratio of CO/O 2 is 1:1) under the realistic application temperature range (130–200 °C), and remains catalytically stable during 65 h testing at 140 °C. A combination of detailed characterizations and density functional theory (DFT) simulations show that Fe species can avoid the co-adsorption of O 2 on the Pt sites by providing more oxygen vacancy to activate O 2 , while K species will further enhance the adsorption of CO and repulse the adsorption of H 2 on Pt surface. Therefore, the optimized adsorption of CO, O 2 and H 2 results in a total CO conversion and high CO 2 selectivity in high temperature range. [ABSTRACT FROM AUTHOR]