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[Display omitted] • Hydrodeoxygenation of phenol in gas phase over Pd-VO x /SiO 2 catalysts. • Pd/SiO 2 promotes hydrogenation pathways whereas VO x addition favors deoxygenation. • Deoxygenation depends on the contact between V3+ and V4+ cations and metal particle. • Pd-VO x interface is responsible for the activation of the C = O bond. This work investigates the effect of vanadia species on the performance of Pd/VO x /SiO 2 catalysts containing different vanadia loadings for HDO of phenol in the gas phase. in situ XANES experiments reveal the presence of a mixture of V 2 O 4 and V 4 O 7 species for all catalysts after reduction at 573 K. In situ XRD and XANES demonstrate that Pd particles and VO x species are in close contact, which is likely due to the presence of polymerized vanadate species, regardless of vanadia content, as shown by UV–Vis spectroscopy. This close contact promotes the selective hydrogenation of the C = O bond or the cleavage of the C-O bond, producing benzene. The strong interaction between the oxygen of the tautomer intermediate molecule and the oxygen vacancies associated with the presence of V3+ and V4+ cations is responsible for the deoxygenation activity of Pd/VO x /SiO 2 catalysts. [ABSTRACT FROM AUTHOR]

Herein, we explore how OH groups on Pt/γ‐AlOOH and Pt/γ‐Al2O3 catalysts affect CO2 hydrogenation with H2 at temperatures from 250°C to 400°C. OH groups are abundant on γ‐AlOOH, but rare at Pt‐(γ‐AlOOH) interface which is the most favorable site for CO2 conversion on Pt/γ‐AlOOH. This makes CO2 hydrogenation on Pt/γ‐AlOOH form CO weakly bonding to γ‐AlOOH, which prefers to desorption from Pt/γ‐AlOOH rather than further conversion, thus enhancing CO production on Pt/γ‐AlOOH. Different from Pt/γ‐AlOOH, OH groups are abundant at Pt‐(γ‐Al2O3) interface which is the most favorable site for CO2 conversion on Pt/γ‐Al2O3. This promotes CO2 hydrogenation on Pt/γ‐Al2O3 to form CO strongly bonding to Pt, which prefers to further hydrogenation to CH4, and thereby increases CH4 selectivity on Pt/γ‐Al2O3. Therefore, the OH groups at metal‐support interface are crucial factor influencing product distribution, and must be considered seriously when fabricating catalysts. [ABSTRACT FROM AUTHOR]

In this work, a commercial P25 (TiO2) with phase junctions between (101) and (110) faces supported Pt catalyst was prepared for glycerol selective oxidation, giving a decent 76.8% glyceric acid (GLYA) yield, and good stability. The kinetic experiments calculated apparent activation energy, turnover frequency (TOF), and reaction rates, demonstrating Pt/P25 could facilitate glyceraldehyde (GLYAD) formation and inhibit GLYA over‐oxidation. Series of structural techniques confirmed the 101/110 junctions in P25 contributed electronic effect on Pt through metal‐support interface, which improved the oxygen activation ability and optimized the GLYAD/GLYA adsorption modes. Furthermore, progressive scale‐up reactions were tested and the mass transfer limitations under different conditions were thoroughly studied. The obtained mass transfer factors suggested the gas–liquid and liquid–solid mass transfer were severely limited. Finally, through optimizing the conditions, Pt/P25 catalyst achieved 75.8% GLYA yield at 300 ml‐scale reaction, realizing equivalent magnification with the 5 ml‐scale experiment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Cu-Co/CeO x catalysts were prepared by reduction of CuCoCe-LDH. • CoCe-Vö interface structure and H 2 spillover effect were investigated. • DFT calculations reveal that CoCe-Vö interface could activate C O bond of MFA. • >95% of DMF yield was obtained over the Cu 1 -Co 8 /CeO x catalyst. The interface site between metal and support possess unique electronic and morphological structure, providing distinct active centers for favorable reaction in catalytic conversion of biomass derivatives to valuable chemicals. In this study, a series of Cu-Co/CeO x catalysts were prepared for hydrogenolysis of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) via reduction of the corresponding layered double hydroxide precursors. The characterizations indicated the formation of CoCe-Vö interface (Vö denotes oxygen vacancy) and the effect of hydrogen spillover from Cu species to CoCe-Vö interface. Furthermore, the experiments and theoretical calculations verified that CoCe-Vö interface could activate the C O bond. The optimized catalyst showed a DMF yield of > 90% at 180 °C and 1.5 MPa H 2 with no deactivation in the cycling tests. This study reveals the interfacial effects of the nanocatalysts, including the oxygen vacancies and hydrogen spillover, on hydrogenolysis of HMF, which provided a simple and efficient approach for synthesis of high-performance non-noble metal nanocatalysts applied to the hydrogenolysis of various biomass derivatives. [ABSTRACT FROM AUTHOR]

The production of nitrous oxide, N2O, via NH3 oxidation is not on a practical scale due to the lack of a suitable catalyst. Instead, it is produced via thermal decomposition of NH4NO3, rendering N2O too costly and limiting its prospective uses. Herein, we report CeO2‐supported Au nanoparticles (2–3 nm) as a highly selective catalyst for low‐temperature NH3 oxidation to N2O, exhibiting two orders of magnitude higher space–time yield than the state‐of‐the‐art Mn−Bi/α‐Al2O3 and remarkable stability over 70 h on stream. The reaction proceeds via a Mars–van Krevelen mechanism, with the density of interfacial Auδ+ species and the oxygen storage capacity of CeO2 identified as the key performance descriptors. The latter could be enhanced by cobalt doping, improving the catalytic activity and setting a new benchmark for N2O productivity. These findings establish NH3 oxidation as an efficient process for N2O manufacture and facilitate its broader utilization in selective oxidations. [ABSTRACT FROM AUTHOR]

H2 adsorption on Au catalysts is weak and reversible, making it difficult to quantitatively study. We demonstrate H2 adsorption on Au/TiO2 catalysts results in electron transfer to the support, inducing shifts in the FTIR background. This broad background absorbance (BBA) signal is used to quantify H2 adsorption; adsorption equilibrium constants are comparable to volumetric adsorption measurements. H2 adsorption kinetics measured with the BBA show a lower Eapp value (23 kJ mol−1) for H2 adsorption than previously reported from proxy H/D exchange (33 kJ mol−1). We also identify a previously unreported H‐O‐H bending vibration associated with proton adsorption on electronically distinct Ti‐OH metal‐support interface sites, providing new insight into the nature and dynamics of H2 adsorption at the Au/TiO2 interface. [ABSTRACT FROM AUTHOR]

[Display omitted] • Alkyltriethoxysilane (C n TES) was grafted onto commercial Al 2 O 3 prior to Ni loading. • The maximum quantity of grafted C n TES depended on the surface properties of Al 2 O 3. • The alkyl substituent of grafted C n TES influenced Ni dispersion and reducibility. • Ni particles became smaller and more metallic with increasing Si/Al ratio. • C 3 TES was the most effective for active Ni catalysts among the C n TES materials. Tuning metal–support interface in supported Ni catalysts is a promising approach for overcoming the agglomeration of Ni particles and the low reducibility of Ni species. This study describes a facile two-step method to produce active Ni catalysts for the hydrogenation of benzyltoluene. In the first step, alkyltriethoxysilanes (C n TES, n = 1, 3, and 8) were grafted onto the surface of commercial Al 2 O 3. The maximum Si/Al ratio of the prepared C n TES-on-Al 2 O 3 materials was determined to be approximately 2.9 mol.%, which can vary depending on the surface properties of Al 2 O 3. The second step was H 2 reduction of the Ni precursor loaded on the C n TES-on-Al 2 O 3 materials to remove alkyl substituents from the grafted C n TES and form Ni particles on the surface of silica grafted onto alumina (SGA). The hydrogenation performance of the obtained Ni/SGA_C n TES catalysts was improved with increasing Si/Al ratio owing to higher Ni dispersion and more abundant metallic Ni. The activity of the Ni/SGA_2.9C n TES (Si/Al = 2.9 mol.%) catalysts exhibited a volcano-shaped relationship with the length of the alkyl substituent of grafted C n TES, reaching the maximum for C 3 TES. Notably, Ni/SGA_2.9C 3 TES showed excellent ability for the adsorption of H 2 and substrate, as well as high stability, resulting from the reduced agglomeration of Ni particles and the modulated metal–support interface. Therefore, the demonstrated synthesis approach can render Ni catalysts servable to promote the commercialization of liquid organic hydrogen carrier system. [ABSTRACT FROM AUTHOR]

Ammonia Oxidation, Au/CeO2, Metal-Support Interface, Nitrous Oxide, Reaction Mechanisms Keywords: Ammonia Oxidation; Au/CeO2; Metal-Support Interface; Nitrous Oxide; Reaction Mechanisms EN Ammonia Oxidation Au/CeO2 Metal-Support Interface Nitrous Oxide Reaction Mechanisms 1 1 1 04/27/22 20220502 NES 220502 B A game of two halves b Direct ammonia oxidation unlocks a pathway towards affordable and efficient production of nitrous oxide, a highly promising agent for selective oxidation reactions, but necessitates the development of suitable catalysts. Back Cover: Ceria-Supported Gold Nanoparticles as a Superior Catalyst for Nitrous Oxide Production via Ammonia Oxidation (Angew. [Extracted from the article]

Keywords: Ammonia Oxidation; Au/CeO2; Metal-Support Interface; Nitrous Oxide; Reaction Mechanisms EN Ammonia Oxidation Au/CeO2 Metal-Support Interface Nitrous Oxide Reaction Mechanisms 1 1 1 04/27/22 20220502 NES 220502 B Ein Spiel zweier Hälften b Die direkte Oxidation von Ammoniak eröffnet einen Weg zur kostengünstigen und effizienten Produktion von Stickstoffoxid, einem vielversprechenden Reagens für selektive Oxidationsreaktionen. Rücktitelbild: Ceria-Supported Gold Nanoparticles as a Superior Catalyst for Nitrous Oxide Production via Ammonia Oxidation (Angew. Ammonia Oxidation, Au/CeO2, Metal-Support Interface, Nitrous Oxide, Reaction Mechanisms. [Extracted from the article]

Abstract: A glow discharge plasma treatment was used to modify the impregnation method to prepare photocatalysts with the following steps: impregnation, cold plasma treatment, calcination, and reduction. The activity and properties of the catalysts were studied in comparison with those prepared with traditional impregnation method. The activities for hydrogen generation from water/alcohols mixtures were significantly promoted. The properties including the metal dispersion, near-UV absorption, and metal stability were also enhanced. The enhanced metal dispersion and optical absorption partly promoted the activity but the effect was limited. It was speculated that the plasma method produced an enhanced metal–support interaction. According to high-resolution TEM observation, a greatly distorted metal–support interface was formed on the plasma prepared catalyst. This interface allowed a close contact between the metal atoms and support lattices, which supported the existence of the enhanced interaction. This interface was expected to facilitate the electron transfer during photocatalytic reaction and be the major reason for the high activity of the plasma prepared photocatalysts. [Copyright &y& Elsevier]

• Hydrodeoxygenation of phenol at gas phase over Pd-NbO x /SiO 2 catalysts. • Pd/SiO 2 promotes hydrogenation pathways whereas addition of Nb favors deoxygenation. • Deoxygenation depended on the contact between Nb cations and metal particle. • Pd-NbO x interface is responsible for the activation of the C O bond. In this work, the effect of interfacial sites between Pd particles and Nb 2 O 5 species is investigated by testing a series of Pd-Nb 2 O 5 /SiO 2 catalysts with different niobium loadings for the HDO reaction of phenol in the gas phase. Important differences in the selectivity to deoxygenated product were observed depending on the presence of niobium oxide close to Pd particles, which reveals the key role of the type of active phase in the control of reaction steps. It was found that Pd/SiO 2 catalyst promotes hydrogenation pathways, producing cyclohexanone as the major product. For Pd-Nb 2 O 5 /SiO 2 catalyst containing a Nb/Pd molar ratio of 0.5, a sharp increase in the selectivity to benzene is observed (7.5-fold). Increasing the Nb/Pd molar ratio, the formation of benzene is enhanced. The results showed that the Pd-Nb 2 O 5 interface, composed by an oxophilic oxide in the perimeter of the metal particle, is responsible for the activation of the C O bond, promoting the deoxygenation reaction. [ABSTRACT FROM AUTHOR]