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Here, we report a visible promotion effect of the B2O3 additive on FeOx/Si3N4 catalysts in the oxidative dehydrogenation of ethylbenzene. The oxygen reactivity of FeOx was alleviated by the strong interaction between FeOx and BOx species, which suppresses the overoxidation of ethylbenzene and styrene to carbon oxides, thus promoting styrene selectivity. [ABSTRACT FROM AUTHOR]

The production of acetaldehyde through biomass‐derived ethanol dehydrogenation is a sustainable alternative compared to the fossil‐feedstock based process, for which Cu‐based catalysts are considered to be the most efficient. Herein, we modified the surface of silicon carbide (SiC) to alter the properties of the interface from SiO2‐rich to C‐rich, and we prepared a series of Cu‐supported catalysts (Cu/SiC, Cu/SiO2/SiC, and Cu/C/SiC) with the aim of insight into the effect of the interface structure and composition on catalytic dehydrogenation of ethanol. At 280 °C, the Cu/SiO2/SiC catalyst exhibits high ethanol conversion due to the excellent dispersion of Cu nanoparticles promoted by SiO2‐rich interface. In contrast, Cu nanoparticles dispersed on C/SiC shows somewhat lower activity but excellent acetaldehyde selectivity with trace amounts of by‐products under identical reaction conditions. This difference is attributed to the fast removal of acetaldehyde because of its low affinity for the relatively inert C‐rich interface (C/SiC). This work provides an in‐depth understanding of Cu−Si−C multi‐interfacial structure and the ethanol dehydrogenation behavior, which may shed light on the design of novel catalysts with tailored interfacial structures. Beyond biomass where copper talks: Cu based catalysts (Cu/SiO2/SiC, Cu/C/SiC) using silicon carbide with tailored interfaces as supports are designed and investigated as active catalysts for biomass‐derived ethanol dehydrogenation. [ABSTRACT FROM AUTHOR]

Abstract: The dehydrogenation of ethanol to acetaldehyde (DHEA) is an environmentally benign alternative for synthetic chemistry and for the fine chemical industry. The key is to design Cu‐based catalysts with certain structures to obtain high acetaldehyde selectivity. Herein, hybrid C@SiO2 hollow submicron spheres were designed and synthesized using a confined pyrolysis method. This hybrid structure processes a layer of carbon‐silica hybrid shell. After loading the Cu, the Cu/C@SiO2 catalyst exhibited 36.1% conversion of ethanol and ∼99% acetaldehyde selectivity at 260 °C. The hybrid support combined the two favorable properties of carbon and silica and thus improving both selectivity and stability. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) has lately received great attention in the oxidative dehydrogenation (ODH) reaction of propane to propylene for its extraordinary olefin selectivity in contrast to metal oxides. However, high crystallinity of commercial h-BN and elusive cognition of active sites hindered the enhancement of utilization efficiency. Herein, four kinds of plasmas (N 2 , O 2 , H 2 , Ar) were accordingly employed to regulate the local chemical environment of h-BN. N 2 -treated BN exhibited a remarkable activity, i.e., 26.0 % propane conversion with 89.4 % selectivity toward olefins at 520 °C. Spectroscopy demonstrated that "three-boron center" N-defects in the catalyst played a pivotal role in facilitating the conversion of propane. While the sintering effect of the "BO x " species in O 2 -treated BN, led to the suppressed catalytic performance (12.4 % conversion at 520 °C)., (© 2021 Wiley-VCH GmbH.)