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Catalytic transfer hydrogenation (CTH) of biomass-derived furfural (FAL) to furfuryl alcohol is recognized as one of the most versatile techniques for biomass valorization. However, the irreversible sintering of metal sites under the high-temperature reaction or during the coke removal regeneration process poses a serious concern. Herein, we present a silicalite-1-confined ultrasmall CuO structure (CuO@silicalite-1) and then compared its catalytic efficiency against conventional surface-supported CuO structure (CuO/silicalite-1) toward CTF of FAL with alcohols. Characterization results revealed that CuO nanoparticles encapsulated within the silicalite-1 matrix are ∼1.3 nm in size in CuO@silicalite-1, exhibiting better dispersion as compared to that in the CuO/silicalite-1. The CuO@silicalite-1, as a result, exhibited nearly 100-fold higher Cu-mass-based activity than the CuO/silicalite-1 counterpart. More importantly, the activity of the CuO@silicalite-1 catalyst can be regenerated via facile calcination to remove the surface-bound carbon deposits, unlike the CuO/silicalite-1 that suffered severe deactivation after use and cannot be effectively regenerated.

High‐temperature pyrolysis of nitrogen (N)‐rich, crystalline porous organic architectures in the presence of a metal precursor is an important chemical process in heterogeneous catalysis for the fabrication of highly porous N‐carbon‐supported metal catalysts. Herein, covalent triazine framework (CTF) and CTF‐I (that is, CTF after charge modulation with iodomethane) are presented as sacrificial templates, for the synthesis of carbon‐supported Ru catalysts—Ru‐CTF‐900 and Ru‐CTF‐I‐900 respectively, following high‐temperature pyrolysis at 900 °C under N2 atmosphere. Predictably, the dispersed Ru on pristine CTF carrier suffered severe sintering of the Ru nanoparticles (NPs) during heat treatment at 900 °C. However, the Ru‐CTF‐I‐900 catalyst is composed of ultra‐small Ru NPs and abundant Ru single atoms which may have resulted from much stronger RuN interactions. Through modification of the micro‐environment within the CTF architecture, Ru precursor interacted on charged‐modulated CTF framework shows electrostatic repulsion and steric hindrance, thus contributing toward the high density of single Ru atoms and even smaller Ru NPs after pyrolysis. A RuRu coordination number of only 1.3 is observed in the novel Ru‐CTF‐I‐900 catalyst, which exhibits significantly higher catalytic activity than Ru‐CTF‐900 for transfer hydrogenation of acetophenone. [ABSTRACT FROM AUTHOR]

Here, a MoOx-T based catalyst was developed by a simple reduction of MoO3 precursors at different temperatures. Interestingly, a partially reduced MoOx-600 catalyst obtained by reducing the MoO3 precursor at 600 °C shows the co-existence of a mixture of different valence states (0, +4, ∼+6) of Mo, and as a result, provides a superior catalytic activity. [ABSTRACT FROM AUTHOR]

In the present study, a sonochemical‐based method for one‐pot synthesis of entropy‐stabilized perovskite oxide nanoparticle catalysts with high surface area was developed. The high‐entropy perovskite oxides were synthesized as monodispersed, spherical nanoparticles with an average crystallite size of approximately 5.9 nm. Taking advantage of the acoustic cavitation phenomenon in the ultrasonication process, BaSr(ZrHfTi)O3, BaSrBi(ZrHfTiFe)O3 and Ru/BaSrBi(ZrHfTiFe)O3 nanoparticles were crystallized as single‐phase perovskite structures through ultrasonication exposure without calcination. Notably, the entropically‐driven stability of Ru/BaSrBi(ZrHfTiFe)O3 with excellent dispersion of Ru in the perovskite phase bestowed the nanoparticles of Ru/BaSrBi(ZrHfTiFe)O3 with good catalytic activity for CO oxidation. [ABSTRACT FROM AUTHOR]

Herein, we present a facile, sustainable, and highly efficient ionic liquid induced self-assembly protocol to construct a highly porous MnNbOx oxide with exceptionally high catalytic activity for NOx removal at low temperatures and excellent tolerance to H2O and SO2 poisoning. [ABSTRACT FROM AUTHOR]

The simultaneous conversion of C5 and C6 mixed sugars into methyl levulinate (MLE) has emerged as a versatile strategy to eliminate costly separation steps. However, the traditional upgrading of C5 sugars into MLE is very complex as it requires both acid‐catalyzed and hydrogenation processes. This study concerns the development of a one‐pot, hydrogenation‐free conversion of C5 sugars into MLE over different acid catalysts at near‐critical methanol conditions with the help of 1,3,5‐trioxane. For the conversion of C5 sugars over zeolites without the addition of 1,3,5‐trioxane, the MLE yield is quite low, owing to low hydrogenation activity. The addition of 1,3,5‐trioxane significantly boosts the MLE yield by providing an alternative conversion pathway that does not include the hydrogenation step. A direct comparison of the catalytic performance of five different zeolites reveals that Hβ zeolite, which has high densities of both Lewis and Brønsted acid sites, affords the highest MLE yield. With the addition of 1,3,5‐trioxane, the hydroxymethylation of furfural derivative and formaldehyde is a key step. Notably, the simultaneous conversion of C5 and C6 sugars catalyzed by Hβ zeolite can attain an MLE yield as high as 50.4 % when the reaction conditions are fully optimized. Moreover, the Hβ zeolite catalyst can be reused at least five times without significant change in performance. [ABSTRACT FROM AUTHOR]

Herein, we present a facile, sustainable, and highly efficient ionic liquid induced self-assembly protocol to construct a highly porous MnNbOx oxide with exceptionally high catalytic activity for NOx removal at low temperatures and excellent tolerance to H2O and SO2 poisoning. [ABSTRACT FROM AUTHOR]

Here, a MoO x -T based catalyst was developed by a simple reduction of MoO 3 precursors at different temperatures. Interestingly, a partially reduced MoO x -600 catalyst obtained by reducing the MoO 3 precursor at 600 °C shows the co-existence of a mixture of different valence states (0, +4, ∼+6) of Mo, and as a result, provides a superior catalytic activity.

Herein, we present a facile, sustainable, and highly efficient ionic liquid induced self-assembly protocol to construct a highly porous MnNbOx oxide with exceptionally high catalytic activity for NOx removal at low temperatures and excellent tolerance to H2O and SO2 poisoning.