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Developing high‐performance aviation fuel is highly desired for the rapid development of supersonic aircraft. Herein, selective deep hydrogenation of polycyclic aromatics to a high‐density fuel is developed over a Ru‐based catalyst. The influences of strong Ru‐support interaction on tailoring the reaction pathways of acenaphthene hydrogenation were investigated using different oxide supports (SiO2, CeO2, TiO2). Ru/CeO2 and Ru/TiO2 with strong SMSI possess abundant electron‐deficient Ruδ+ species which exhibit a good ability to promote H2 dissociation and increase the isomerization rate of saturated aromatic compounds. Due to the enhanced adsorption of aromatic molecules, Ru/CeO2 (1.30 μmol min−1 g−1) exhibits superior catalytic activity in comparison to Ru/TiO2 (1.25 μmol min−1 g−1) during acenaphthene hydrosaturation, while Ru/TiO2 exhibits the highest isomerization reaction rate (7.60×10−2 μmol min−1 g−1) because of its excellent hydrogen spillover ability and high content of Ruδ+ species. The best catalytic activity with 96 % selectivity of ccc‐perhydroacenaphthene was achieved on Ru/TiO2, and an isomerization mechanism of perhydroacenaphthene isomers was proposed. [ABSTRACT FROM AUTHOR]

Three kinds of Pt nanocrystals with different morphologies (5 nm cubes, 10 nm cubes and 5 nm truncated octahedrons) were synthesized and employed to fabricate Pt/CNT-USY catalysts for selective ring opening of decalin. The 5 nm truncated octahedral Pt/CNT-USY with exposed (100) and (111) facets exhibited higher yield of ring-opening products (53.9 wt%) than the CNT-USY-supported 5 nm cubic Pt catalyst enclosed by the (100) facets (39.6 wt%). Moreover, the 5 nm cubic Pt showed better catalytic activities compared to the 10 nm cubic Pt/CNT-UST catalyst, which ascribed to the smaller size of Pt NCs enriched more revealable metal active sites. DFT calculations demonstrated that the adsorption of decalin on Pt (111) was stronger than that on Pt (100) facets, which was profitable for the selective ring-opening reaction. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been widely studied for electrochemical CO2 reduction reaction (CO2RR). However, the application of negative potential tends to trigger its structural reconstruction and component alteration. It is of great significance to study the relationship between the structural evolution of MOF‐derived materials and product selectivity under the reaction conditions. Herein, we fabricate a HKUST‐1 thin film on carbon fiber paper by a facile electrodeposition approach to investigate the variation of CO2RR activity with HKUST‐1 structural reconstruction. During the CO2RR process, the HKUST‐1 reconstructs into two structures successively over time: 3D nanospheres composed of numerous small fragments and 3D nano‐network composed of cross‐linked nanobelts in different directions. The former shows a better catalytic activity due to more active sites, lower charge transfer resistance and higher Cu+/Cu0 ratio. The optimum Faradaic efficiency (FE) of C2 products (ethylene and ethanol) reaches 58.6 % at −0.98 V versus reversible hydrogen electrode (RHE). [ABSTRACT FROM AUTHOR]

Hollow Silicalite-1 and ZSM-5 zeolites with hierarchical porous shells have been synthesized by using a dissolution-recrystallization method. The morphology, structure, and acidity of these zeolites supported Pt catalysts were characterized by XRD, FT-IR, MAS-SSNMR, FE-SEM, FE-TEM, N2-BET, XPS, NH3-TPD, and CO pulse chemisorption. Compared to the conventional ZSM-5 supported Pt catalyst, the special structure in hollow ZSM-5 zeolite significantly promotes the dispersion of metallic Pt and the synergistic effect between metal active sites and acid sites. These boost the catalytic activity, selectivity of guaiacol hydrodeoxygenation toward cycloalkanes and long-term stability over the Pt/hollow ZSM-5 catalyst combined with improved mass transfer of products and reactants derived from the hierarchical hollow porous structure. Moreover, the Pt/hollow ZSM-5 catalyst exhibits excellent low temperature catalytic activity to completely transform guaiacol into cycloalkanes with the cyclohexane selectivity of more than 93% at 220 °C, suggesting that hollow ZSM-5 zeolite is a promising support for upgrading of bio-oils. [ABSTRACT FROM AUTHOR]

[Display omitted] • The metal-acid sites intimacy was regulated by strong electrostatic adsorption. • Hydroisomerization and hydrocracking mechanisms were altered via tailoring the metal-acid sites intimacy. • Nanoscale metal-acid sites intimacy reduced acid steps (n as). • The isomerization selectivity showed a linear decease with the increase of n as values. • Fewer acid steps were beneficial to the pore mouth mechanism. Designing a bifunctional catalyst to achieve efficient hydroisomerization of long-chain alkanes is very essential for producing high-performance fuel and lubricant base oils. Herein, a bifunctional catalyst composed of an intimate mixture of ZSM-48 zeolite and alumina binder and with platinum (Pt) metal controllably deposited on zeolite or alumina was fabricated by a strong electrostatic adsorption method. The dependence of reaction pathways of hydroisomerization and hydrocracking of n -hexadecane on the metal-acid sites intimacy was investigated. High Brønsted acid density and suitable metal-acid sites intimacy favored to promote the catalytic activity. The selectivity, hydroisomerization mechanism and hydrocracking mechanism were significantly altered by tailoring the metal-acid sites intimacy. Too large or too small metal-acid sites intimacy was conducive to inhibit the occurrence of pore-mouth mode. A linear decease of the hydroisomerization selectivity with the increase of acid steps (n as) was observed. The catalyst with nanoscale intimacy of metal-acid sites (Pt/A-48) showed the highest catalytic activity and isomer selectivity (87%) and the least acid steps (n as = 1.4). This work provides a promising approach to fabricating highly efficient and shape-selective bifunctional catalysts for selective hydroisomerization of long-chain alkanes. A reaction network was proposed over the catalysts with different metal-acid intimacy. [ABSTRACT FROM AUTHOR]

• Hollow IrCoO x structure is fabricated via a sample in-situ reconstruction strategy. • The unique hollow structure exposes more active sites and increases the active area. • The IrO x -rich shell is enriched in crystalline/amorphous and atomic heterointerface. • Hollow structure and heterointerface are beneficial to improve OER performance. • Hollow Ir 0.16 Co 0.84 O x presents excellent mass activity of 1032.16 A g Ir -1. Iridium oxide (IrO x)-based materials perform high efficiency and durability for oxygen evolution reaction (OER) in acidic environment. Developing highly efficient OER electrocatalysts with low Ir-loading in acid is still a great challenge. Herein, we fabricated a hollow IrCoO x nanosphere via in-situ electrochemistry reconstruction strategy. The developed hollow Ir 0.16 Co 0.84 O x electrocatalyst with low Ir-loading (51.91 μg cm−2) exhibits 71-fold and 42-fold improvement in OER mass activity and TOF value compared with commercial IrO 2 (1032.16 vs 14.44 A g Ir −1, 0.754 vs 0.018 s−1) in 0.1M HClO 4 , respectively. Combining with the analysis of the IrCoO x structure, the electrochemical performance reveals that the superior activity ascribes to the favorable hollow structure, the abundant crystalline/amorphous heterostructure in the IrO x -enriched shell and the atomic heterointerfaces between Co and Ir oxides, which increase the electrochemical active area, accelerate the OER kinetics and lower the charge transfer resistance (2.8 Ω cm2). This work is anticipated to aid the design of novel low Ir-loading electrocatalysts with outstanding catalytic activity for water splitting in acidic environments. [Display omitted] [ABSTRACT FROM AUTHOR]