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Osteoarthritis (OA) is a prevalent degenerative joint disease with a lack of effective therapeutic. Chondrocyte ferroptosis contributes to the progression of OA. PUM2 is shown to exacerbate ischemia–reperfusion‐induced neuroinflammation by promoting ferroptosis, but its role in OA remains unexplored. Here, primary mouse chondrocytes were stimulated with IL‐1β to mimic OA chondrocyte injury in vitro. And PUM2 was upregulated in OA cartilage tissues and IL‐1β‐induced chondrocytes. Silencing PUM2 alleviated IL‐1β‐induced chondrocyte inflammation and ECM degradation. Mechanistically, PUM2 facilitated the degradation of NEDD4 mRNA by binding to the 3′UTR of NEDD4 mRNA, which in turn inhibited NEDD4 induced PTEN ubiquitination and degradation. Consistently, NEDD4 silencing reversed the ameliorative effect of PUM2 knockdown on chondrocyte injury, and overexpression of PTEN abolished the improved role of NEDD4 in chondrocyte injury. Moreover, PTEN aggravated IL‐1β‐induced ferroptosis in chondrocytes through the Nrf2/HO‐1 pathway by increasing the levels of Fe2+, ROS, MDA, and ACSL4 protein, decreasing the activity of SOD and the levels of GSH and GPX4 protein, and aggravating mitochondrial damage. Additionally, destabilized medial meniscus (DMM) were conducted to establish the OA mouse model, and adenovirus‐mediated PUM2 shRNA was administered intra‐articularly. Silencing PUM2 attenuated OA‐induced cartilage damage in vivo. In conclusion, PUM2 promoted OA progression through PTEN‐mediated chondrocyte ferroptosis by facilitating NEDD4 mRNA degradation. [ABSTRACT FROM AUTHOR]

Multifunctional metasurfaces have demonstrated extensive potential in various fields. During the design of metasurfaces, optimization of components for polarization, amplitude distribution, phase distribution, and other factors is necessary. This process typically demands expert involvement and is time‐consuming. In this paper, a metasurface inverse design method is introduced that combines a high‐precision ultra‐wideband spectrum forward prediction utilizing a neural network and a genetic algorithm. A neural network is constructed and trained to accurately predict the amplitude and phase of a 16 × 16 discrete grid structure with high degrees of freedom in the frequency range of 0.5–2 THz. Leveraging the neural network's ultra‐fast spectrum prediction capabilities (producing approximately 1000 spectra per second), the average optimization time for a single component is reduced to 1.5 min. Finally, the effectiveness of this inverse design method is validated through the design and simulation of multifunctional reflective deflection metasurfaces with two sets of 3‐bit frequency multiplexing and polarization multiplexing. The proposed metasurface inverse design method offers a new approach for the rapid design of components in complex application scenarios and holds significant reference value for metasurface designers. [ABSTRACT FROM AUTHOR]

The development of low‐cost nickel‐based catalysts for direct and selective hydrogenation of 2‐butyne‐1,4‐diol (BYD) to butane‐1,4‐diol (BAD) under mild conditions is an important and attractive target both in fundamental research and industrialization but remains a formidable challenge. The primary industrial production method for BAD synthesis is a two‐step reaction route, which suffers from complicated catalysis conditions and high equipment costs. Herein, we develop a high‐performance catalyst via a facile alcohol‐treated strategy for highly selective BAD synthesis at moderate operation conditions. The as‐synthesized NA‐80E catalyst exhibits outstanding BAD selectivity of 98.82 % and BYD conversion of 100 % at 60 °C and 4 MPa, outperforming most reported results for BAD formation in a one‐step process and even being comparable to those obtained by the two‐step hydrogenation reaction route under much high temperatures and pressures. Crucially, we found that after facile alcohol (ethanol) treatment, an intriguing phenomenon of suppression of adjacent acid‐assisted hydrogenolysis via extra acidic Al species at the NiO‐Al2O3 interface is observed, contributing to the precise enhancement of BAD selectivity by inhibiting the production of butanol (BOL). This facile alcohol‐treated method along with the revealed mechanism of blocked hydrogenolysis opens vast possibilities for designing high‐performance and highly‐selective hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

The conversion of CO2 into ethanol with renewable H2 has attracted tremendous attention due to its integrated functions of carbon elimination and chemical synthesis, but remains challenging. The electronic properties of a catalyst are essential to determine the adsorption strength and configuration of the key intermediates, therefore altering the reaction network for targeted synthesis. Herein, we describe a catalytic system in which a carbon buffer layer is employed to tailor the electronic properties of the ternary ZnOx−Fe5C2−Fe3O4, in which the electron‐transfer pathway (ZnOx→Fe species or carbon layer) ensures the appropriate adsorption strength of −CO* on the catalytic interface, facilitating C−C coupling between −CHx* and −CO* for ethanol synthesis. Benefiting from this unique electron‐transfer buffering effect, an extremely high ethanol yield of 366.6 gEtOH kgcat−1 h−1 (with CO of 10 vol % co‐feeding) is achieved from CO2 hydrogenation. This work provides a powerful electronic modulation strategy for catalyst design in terms of highly oriented synthesis. [ABSTRACT FROM AUTHOR]

Natural materials are composed of a limited number of molecular building blocks and their exceptional properties are governed by their hierarchical structure. However, this level of precision is unattainable with current state‐of‐the‐art materials for 3D printing. Herein, new self‐assembled printable materials based on block copolymers (BCPs) enabling precise control of the nanostructure in 3D are presented. In particular, well‐defined BCPs consisting of poly(styrene) (PS) and a polymethacrylate‐based copolymer decorated with printable units are selected as suitable self‐assembled materials and synthesized using controlled radical polymerization. The synthesized library of BCPs are utilized as printable formulations for the fabrication of complex 3D microstructures using two‐photon laser printing. By fine‐tuning the BCP composition and solvent in the formulations, the fabrication of precise 3D nano‐ordered structures is demonstrated for the first time. A key point of this work is the achievement of controlled nano‐order within the entire 3D structures. Thus, imaging of the cross‐sections of the 3D printed samples is performed, enabling the visualization also from the inside. The presented versatile approach is expected to create new avenues for the precise design of functional polymer materials suitable for high‐resolution 3D printing exhibiting tailor‐made nanostructures. [ABSTRACT FROM AUTHOR]

Zn‐Cr‐based catalysts are widely used as oxide catalysts for syngas aromatization, and it is difficult to study the synergistic effect of ZnO and Zn‐Cr spinel due to the complex system of non‐stoichiometric Zn‐Cr spinels. In order to reveal the synergistic effect, we physically mixed ZnO and ZnCr2O4 with definite structure to avoid ambiguous structure of non‐stoichiometric Zn‐Cr spinels. The results showed that the introduced ZnO affected the oxygen vacancies generation and promoted the activation of CO and H2, leading to an increase of oxygenates compared to the sole ZnCr2O4. Due to the synergy of ZnO and ZnCr2O4, the xZZC catalysts could produce more adsorbed species than the ZnCr2O4 catalyst, while the ZnCr2O4/ZSM‐5 catalyst was more difficult to convert formate species. The ZnO in xZZC/ZSM‐5 decreased the formate adsorption strength, which favored the continued conversion of formate and further realized the enhanced pulling effect on CO conversion. [ABSTRACT FROM AUTHOR]

Dispersion is one of the key performances of optical systems. As a man‐made device, metasurface is a notable alternative for dispersion manipulation and has been developed vigorously in recent years. However, the currently reported dispersion manipulation principle of meta‐atoms only relies on controlling the propagation phase in the operation frequency band or several working wavelengths. In this paper, the chirality‐assisted phase is introduced as an additional degree of freedom to engineer the dispersion characteristics of the meta‐atom, and the strategy is theoretically demonstrated. The dispersion characteristic of the chiral meta‐atom working in a reflective manner is discussed in detail within the working bandwidth. Then, two hybrid dispersion‐engineered metamirrors (HDEMs) are proposed and constructed to demonstrate versatile dispersion manipulation in the working frequency band, including achromatic focusing for the lower half band and hyper dispersive focusing for the upper half band, and hyper dispersive focusing and abnormal dispersive focusing in the lower and upper half band, respectively. Both full‐wave simulation and measured performances verify the validity and flexibility of the proposed strategy. This work exploits a new degree of freedom for dispersion manipulation, providing a new approach for dispersion‐engineered metasurfaces design. [ABSTRACT FROM AUTHOR]

BACKGROUND: Syngas conversion to olefins via Fischer‐Tropsch Synthesis (FTs) route and then subsequently into aromatics (syngas−olefins−aromatics (SOA)) was considered a promising industrialization route due to its ability to match reaction temperatures between syngas to olefins (300–400 °C) and olefins to aromatics (300–500 °C). In this reaction route, the syngas to olefin process can be efficiently and easily realized by Fe‐based FTs catalysts. However, the aromatization process occurring over the zeolite catalyst was still considered a big challenge due to zeolites' complex topology, variable morphology, and elusive acidic properties. RESULTS: A series of ZSM‐5 zeolites with different morphologies, including nano ellipsoid, nano cube, nano aggregate, nano bead, and nano pile were successfully synthesized. The effects of the ZSM‐5 zeolite's morphology and reaction temperature on the aromatics synthesis from syngas based on a modified FTs route were systematically studied. CONCLUSION: In all the studied ZSM‐5 zeolites, the nano cube ZSM‐5 zeolite (Z5‐NC) zeolite had the best aromatization ability. The hybrid catalyst combination of FeMnK&Z5‐NC obtained the highest xylene selectivity of 12% (2.8% + 9.2%), and its total aromatics selectivity was also the highest (42.5%). The study on reaction temperature suggested that a higher reaction temperature (320–360 °C) could efficiently impede the formation of CO2. However, the selectivity of aromatics was restrained to around 44% at higher temperatures because a high temperature facilitated the hydrocracking of higher hydrocarbons, leading to the increase of the selectivity of lighter CH4 and paraffin. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The non‐petroleum synthesis route of ethanol from syngas (H2+CO) with methyl acetate (MA) as the core intermediate product has been confirmed as an excellent industrialization route for high purity ethanol production. However, as the central part of this tandem‐catalysis path, the carbonylation of dimethyl ether (DME) to MA is limited by the undesirable catalytic activity and stability of zeolite catalysts. Herein, a facile inhibitor‐assisted strategy was developed for constructing self‐assembled nano‐Mordenite (nano‐MOR) zeolites without using any expensive or complex template. A nano‐filamentous MOR zeolite with only 70 nm crystal diameter was successfully synthesized by selectively controlling the crystal growth orientation with a specific inhibitor. The catalytic performance of self‐assembled nano‐MOR catalysts was remarkably outstanding in DME carbonylation reaction. The highest Space‐Time Yield (STY) of MA was achieved over Nanofilament MOR (NF‐MOR), which was significantly improved comparing with that of the traditional Ellipsoid‐MOR (ES‐MOR) [3780 mmol/(kg ⋅ h) vs. 1368 mmol/(kg ⋅ h)]. One‐step ethanol synthesis was realized by combining the MOR catalyst and an innovative self‐reduced Cu‐ZnO/SiO2 (CZ/SiO2) catalyst in a rationally designed dual‐bed catalysis system. Adopting the tailor‐made NF‐MOR&CZ/SiO2 combination, it obtained the highest STY of ethanol, about 4 times of the conventional ES‐MOR&CZ combination [1800 mmol/(kg ⋅ h) vs. 476 mmol/(kg ⋅ h)]. The present self‐assembled nano‐MOR zeolites synthetic strategy opens a new way for the fabrication of high‐performance zeolites for practical industrial applications in catalytic conversions of one‐carbon (C1) small molecules to high value‐added chemicals. [ABSTRACT FROM AUTHOR]

There are few reports about purely organic phosphorescence scintillators, and the relationship between molecular structures and radioluminescence in organic scintillators is still unclear. Here, we presented isomerism strategy to study the effect of molecular structures on radioluminescence. The isomers can achieve phosphorescence efficiency of up to 22.8 % by ultraviolet irradiation. Under X‐ray irradiation, both m‐BA and p‐BA show excellent radioluminescence, while o‐BA has almost no radioluminescence. Through experimental and theoretical investigation, we found that radioluminescence was not only affected by non‐radiation in emissive process, but also highly depended on the material conductivity caused by the different molecular packing. This study not only allows us to clearly understand the relationship between the molecular structures and radioluminescence, but also provides a guidance to rationally design new organic scintillators. [ABSTRACT FROM AUTHOR]

Accelerating propane dehydrogenation in propane aromatization is vital because it is the first and rate control step. In this study, we introduced Cr to Ga/ZSM‐5 by tuning its impregnation sequence and amount, which was expected to accelerate the dehydrogenation step and improve aromatization performance. The impregnation sequence of Cr on catalyst not only affected the interaction between Ga and ZSM‐5, but also tuned the amount of dehydrogenation active species Cr3+. Due to the plenty of Cr3+ species and strong interaction between Ga species and ZSM‐5, 2Cr/GaZ5 catalyst accelerated the dehydrogenation step and improved the aromatization process. More light hydrocarbons were preferred to be produced and were further converted into BTX on 2Cr/GaZ5 catalyst. Excessive Cr on catalyst caused the formation of Cr2O3 particles with worse dispersion. The aggregated Cr2O3 decreased the strong acidity of catalyst, which could not further promote propane conversion and decreased the aromatization ability of catalyst. [ABSTRACT FROM AUTHOR]

Massive CO2 emission has led to a series of ecological and environmental problems. Sustainable conversion and utilization of CO2 is one of the focuses of today's society. However, the inertness of CO2 molecules and weak chain growth ability limit the efficient utilization of CO2. Herein, different from conventional Fe‐based catalysts, a series of bimetallic catalysts (FeCo) were prepared to investigate the effects of cobalt species existence on catalytic yield of CO2 hydrogenation. The existence of cobalt promotes the formation of small‐size iron carbides. Meanwhile, a suitable surface composition of Co (2.4 at. %) and Fe (7.4 at. %) element is helpful to promote the selective generation of C2+ products, thus presenting a high yield (Co/Fe@C‐8). This study can provide a systematic guidance to the utilization of high‐efficiently bimetallic catalysts for higher hydrocarbon formation with high yield from CO2. [ABSTRACT FROM AUTHOR]

An oxide‐zeolite (ZnCr2O4‐ZSM‐5) catalyst for directly converting CO2 to aromatics was designed and developed. It showed high PX/X (the C‐mol ratio of p‐xylene to all xylene) and PX/aromatics (the C‐mol ratio of p‐xylene to aromatics) ratios, which reached 97.3 and 63.9 %, respectively. [ABSTRACT FROM AUTHOR]

Herein, a simple and green quasi‐solid‐phase (QSP) method for facile synthesis of proton‐type ZSM‐5 avoiding use of excessive water, dry gel, Na+ cation and fluoride is reported. Crystallization by using the stoichiometric amount of TPAOH (tetrapropylammonium hydroxide) at 180 °C for only 12 h gave well‐structured HZSM‐5 crystals with high specific surface area of 429 m2 g−1 and high thermal stability. 5MRs was observed to closely relate the formation of MFI structure and QSP method exhibits shorter induction period (t0), higher nucleation rate (Vn), and faster growth rate (Vg). Moreover, HZ‐12–180 showed extremely better and rather stable catalytic activity for methanol‐to‐propylene reaction by comparison with commercial HZSM‐5. [ABSTRACT FROM AUTHOR]

A Pd/SiO2@S1@H‐ZSM‐5 capsule catalyst (Pd/SiO2–SZ) is fabricated through a dual‐layer crystal growth method with an auxiliary hydrothermal reaction. The catalyst exhibits excellent selectivity to liquefied petroleum gas (LPG) in CO2 hydrogenation reactions, which is attributed to the tandem reactions of methanol synthesis on the Pd/SiO2 core catalyst and methanol dehydration to hydrocarbons on the H‐ZSM‐5 shell. The Pd/SiO2–SZ capsule catalyst has a similar mesoporous structure, narrow range of Pd particles size distribution, and consistent reduction characteristics to the Pd/SiO2 core catalyst. It maintains the physical and chemical properties of the core catalyst throughout the H‐ZSM‐5 shell synthesis process. Energy‐dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy results reveal that the H‐ZSM‐5 zeolite shell completely encapsulates the Pd/SiO2 core catalyst. Compared with the crushed capsule catalyst (Pd/SiO2–SZP), the well‐defined‐structured Pd/SiO2–SZ catalyst has a much higher LPG selectivity of 33.6 %, owing to the well‐matched reactions at the Pd/SiO2 core and H‐ZSM‐5 shell. [ABSTRACT FROM AUTHOR]

Catalytic isobutyl alcohol oligomerization to generate hydrocarbon liquid fuels over zeolite has been investigated over H−Y, SAPO‐34, H‐MOR zeolite and Al‐MCM‐41 catalysts, as a new way to direct conversion of isobutyl alcohol to hydrocarbon liquid fuels, considering the fact that isobutyl alcohol can be obtained from biomass by microbes. In this study, all of the zeolite samples showed good reactivity, especially H‐MOR, achieving 94 % conversion of isobutyl alcohol and 63 % selectivity of C5+ liquid fuels in all products. The effects of reaction conditions including reaction temperature and reaction time were also discussed. The physicochemical properties of the catalysts were characterized by XRD, Nitrogen adsorption‐desorption, NH3‐TPD, TG/DTA, and GS/MS. The reaction system discussed here involves two reactions, i) isobutyl alcohol dehydration reaction via a typical acid catalysis, ii) a polymerization reaction of small molecules into large ones, according to the experimental and characterization results, the pore size and acid property of the zeolite are the two main factors controlling this catalytic dehydration and oligomerization reaction. [ABSTRACT FROM AUTHOR]

This paper investigated the influence of compressive fatigue on the sulfate resistance of slag (0, 20, 50, and 70%) contained concrete under steam curing. After 10,000 cycles loading of 0.5, 0.6, and 0.7 stress level, the concrete was exposed to 5% Na2SO4 for 540 days. The compressive strength, relative dynamic modulus of elasticity (RDME) and SO42− contents were tested after sulfate immersion. Results showed that the standard‐cured fatigued concrete had less strength reduction than the steam‐cured fatigued concrete during sulfate attack. The steam‐cured fatigued concrete containing 20% slag suffered the largest strength reduction, followed by the concrete containing 50, 70, and 0% slag. Compressive fatigue at high stress level (0.7) accelerated the sulfate deterioration of PC standard‐cured concrete, while the effect of low stress level (0.5) was minor. The RDME was not a sensitive indicator to access the sulfate resistance of concrete at the beginning of immersion. Compressive fatigue distinctly promoted the sulfate diffusion; the effective SO42− diffusion coefficient was increased when damage occurred in slag concrete. Besides, based on the fatigue damage, an experimental model of the sulfate deterioration of fatigued concrete was proposed. [ABSTRACT FROM AUTHOR]

Zeolite A with different pore sizes (3 A, 4 A and 5 A) were selected as supports for preparing a series of cobalt catalysts through wetness impregnation method, using NaBH4 as an in‐situ reducing agent, but without further reduction. X‐ray photoelectron spectra (XPS) confirmed the reduction of cobalt. Transmission electron microscopy (TEM) images revealed that the cobalt nanoparticles were formed evenly on the zeolite structure by our rapid synthesis method. The catalytic activity of the prepared catalysts was investigated for the hydroformylation of 1‐hexene. Benefiting from the spatial confinement effect derived from the unique topology structure of zeolite A and the low temperature in‐situ reduction contributed by NaBH4, the conversion of 1‐hexene to C7 aldehyde with a significantly enhanced normal heptanal selectivity (normal/iso ratio of 1.93) was achieved. The present study provides a rapid and effective way for the synthesis of zeolite supported cobalt catalysts for the hydroformylation of 1‐hexene. [ABSTRACT FROM AUTHOR]

The nickel particle size, distribution and interaction with support are crucial to the catalytic performance in dry reforming of methane reaction (DRM). Despite numerous literatures on dry reforming catalysis, the effect of solution pH on the catalytic performance is not well studied. Herein, we designed a series of Ni/SiO2 catalysts with different Ni particle sizes. The Ni particle size was controlled with altering the pH of the Ni nitrate solution via the addition of HNO3 or NH4OH. X‐ray diffraction (XRD) revealed that NH4OH promoted Ni/SiO2 catalysts present smaller NiO nanoparticles, and enhanced metal‐support interaction was evidenced from X‐ray photoelectron spectra (XPS) and H2 temperature‐programmed reduction (H2‐TPR) analyses. In addition, according to thermogravimetric analysis and differential scanning calorimetry (TG‐DSC) and transmission electron microscopy (TEM) results, the spent catalysts produced less carbon deposition and maintained Ni nanoparticles in smaller size after DRM reaction. Catalysts with nearly uniform and small particle size demonstrated a satisfying resistance to aggregation and carbon deposition, while realizing a high CH4, CO2 and Ctotal conversion (74.5, 83.7 and 79.7%, respectively). The present study provides a simple but effective way to change the metal‐support interaction and metal particle size. [ABSTRACT FROM AUTHOR]

A series of CuCoM (M=Fe, Cr, Ga and Al) nanoplates derived from hydrotalcite‐like precursors were synthesized by co‐precipitation method and evaluated for ethanol and higher alcohols (HA) from syngas. The CuCoAl nanoplates demonstrated prominently improved HA selectivity of 54.9 %, and the fraction of ethanol/HA reached up to 55.9 % level. As revealed by XRD and HAADF‐STEM results, the presence of Al species in the CuCoAl nanoplates obviously enhanced the dispersion ability of Cu and Co species. Moreover, the abundance of basic sites (surface hydroxyl groups) on CuCoAl nanoplates resulted in the formation of formate species, which was a significant C1 species for the generation of CHx intermediates. More importantly, a high probability of CO bridge adsorption on metallic Co atoms was found over optimized CuCoAl catalyst, which provided a favorable effect for CO dissociation, leading to the formation of CHx intermediates. Therefore, more CHx intermediates were generated from the formate species and CO bridge adsorption on metallic Co atoms, which provided a beneficial role for C−C chain growth in the higher alcohols production in CO hydrogenation reaction. Furthermore, a moderate ratio of surface Cu/Co was observed over optimized CuCoAl nanoplates, which can exert a synergetic effect between Cu and Co species. Ultimately, the enhanced catalytic performance was attributed to the combination of the Cu and Co species and the basic property of the CuCoAl nanoplates. [ABSTRACT FROM AUTHOR]

The oriented conversion of CO2 into target high‐value chemicals is an effective way to reduce carbon emissions, but still presents a challenge. In this communication, we report the oriented conversion of CO2 into value‐added aromatics, especially para‐xylene, in a single pass by combining core–shell structured Zn‐doped H‐ZSM‐5 (Zn‐ZSM‐5@SiO2) and a Cr2O3 component. Through precise regulation of the acidity of Zn‐ZSM‐5@SiO2, high para‐xylene selectivity (38.7 % in the total products) at a CO2 conversion of 22.1 % was achieved. Furthermore, a CO2‐assisted effect in the synthesis of aromatics during the tandem process has been clarified through a control experiment. The CO2 reactant can act as a hydrogen acceptor to accelerate the dehydrogenation of alkenes, intermediates in the synthesis of aromatics, thereby increasing the driving force towards aromatics in the tandem reaction process. Tandem CO2 conversion: A capsule catalyst with Zn‐doped H‐ZSM‐5 (Zn‐ZSM‐5) as core and amorphous SiO2 as shell (Zn‐ZSM‐5@SiO2) has been prepared and combined with Cr2O3 as a methanol synthesis catalyst to realize the direct conversion of CO2 into value‐added aromatics, especially para‐xylene, in a tandem process (see figure). [ABSTRACT FROM AUTHOR]

As a century‐old classical reaction, Fischer‐Tropsch (F‐T) synthesis is undergoing new developments especially in its applications of producing jet fuel, olefins, aromatics and oxygenated chemicals, which are completely different from the conventional F‐T product, gasoline, diesel and wax. Producing above new products is not obeying famous ASF distribution law, requiring revolutionary design of new F‐T catalysts and reaction pathways. A mass of new research directions on F‐T synthesis for these liquid fuels and high‐value chemicals are successfully proposed. This review spotlights recent new advances based on F‐T synthesis for non‐automotive applications, and discusses its new possible directions in future. Going beyond cars: This Minireview spotlights recent new advances based on Fischer‐Tropsch synthesis for non‐automotive applications, such as jet fuel, olefins, aromatics and oxygenated chemicals, which are completely different from the conventional Fischer‐Tropsch product, and discusses its new possible directions in future. [ABSTRACT FROM AUTHOR]

Zeolite synthesis involved use of large volumes of solvent that resulted in waste and enhanced production costs. In our study, we selected a solvent‐free synthesis route that involved mixing, grinding and crystallization at various times creating Fe@Silicalite‐1. This synthesis method produced a hierarchical in‐situ microporous crystal morphology with Fe particles caged inside zeolite displaying a high gasoline (C5‐C11) selectivity of 66.0% with a relatively low CO2 and CH4 selectivity (18.5% and 10.0%, respectively) in Fischer‐Tropsch synthesis. Prolonged crystallization time of 72 h and other subsequent procedures contributed to zeolite structure and performance. Iron moieties were appropriately immobilized over silicalite support. The characterization results were correlated with the zeolite activity and selectivity. This novel zeolite at its best possesses all the potential to be advanced in other related material synthesis because of its expedient procedure, characteristics and worthwhile outcomes. As a result of solvent‐free synthesis route, this Fe@Silicalite‐1 zeolite containing hierarchical in‐situ microporous crystal structure in union with Fe particles entrapped within zeolite contributed largely to gasoline product distribution of Fischer‐Tropsch synthesis reaction. The remarkable high gasoline selectivity of 66.0% has been achieved by this zeolite as a result of its intrinsic properties. [ABSTRACT FROM AUTHOR]

A bimetallic catalyst combining Fe and Co active sites enables direct conversion of CO2 to hydrocarbons with a higher activity but modest CO selectivity compared with a sole Fe catalyst. The introduction of cobalt metal increases the adsorption ability of CO2, which promotes the CO2 activation over iron species through RWGS reaction. Besides, the carbide content (Fe5C2) also increases significantly with the further introduction of cobalt metal in comparison to potassium modified one, achieving a high C−C bond coupling activity. On the basis, the catalytic performance of CO2 hydrogenation over this bimetallic catalyst was investigated in a two‐stage reactor system, where the influence of number of reactors on CO2 conversion and the catalytic performance over each reactor were analysed regarding the yield of liquid fuel. A significant increase in liquid fuel production was achieved under ordinary conditions. It was proven that ex situ water removal plays the determining role in the integrated process for improving the catalytic activity and lowering the selectivity of undesired CO by‐product. The utilization of a two‐stage reactor system promotes CO2 conversion, making the CO2 conversion approaching a higher value (69.9%). Meanwhile, the yield of liquid fuel exceeds 300 gfuels/(kgcath) under conventional conditions. Catalytic performance of CO2 hydrogenation was conveniently improved via a cobalt‐doped iron‐based catalyst. The enhanced performance for CO2 hydrogenation is ascribed to the improvement of CO2 activation and chain propagation reaction. The two‐stage reactor system with ex situ water removal further provides a straightforward access for enhancing the yield of liquid fuel. [ABSTRACT FROM AUTHOR]

Transition metal sulfides have attracted considerable attention due to their excellent electrochemical performance for supercapacitors. Herein, we prepared a Co3S4/CoMo2S4 (Co−Mo−S) composite on reduced graphene oxide/Ni foam (RGO/NF) with unique flower‐like morphology through a carefully time‐controlled sulfurization process. It was found that the vulcanization time has a great influence on the morphology and electrochemical properties of the composites. After 3 hours of vulcanization, the as‐prepared Co3S4/CoMo2S4@RGO/NF electrode exhibited a superior specific capacitance of 2530.4 F  g−1 at a current density of 1 A g−1, as well as excellent cycling stability with 78.8 % retention of the initial capacitance even after 6,000 cycles at a current density of 10 A g−1. An asymmetric device was assembled employing the Co3S4/CoMo2S4@RGO/NF composite as a positive electrode and activated carbon (AC) as a negative electrode. The device delivered a maximum energy density of 59.0 Wh kg−1 at a power density of 640 W kg−1 and a high cycling performance (90.7 % capacitance retention after 6,000 cycles). These results demonstrate the promising potential of Co−Mo−S@RGO/NF as binder‐free, high‐performance electrode in renewable energy storage systems. A flower‐like Co−Mo−S composite on reduced graphene oxide/Ni foam (RGO/NF) is synthesized. As electrode in an asymmetric supercapacitor, the material shows excellent electrochemical performance. RGO increases the electrical conductivity and provides more active sites. The replacement of oxygen by sulfur and the synergistic effect of Co3S4 and CoMo2S4 make the Co−Mo sulfide promising for applications in electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Abstract: A simplified catalytic system K‐Cu/Al2O3 (KCA‐xCu‐T) with Cu‐Al oxides was prepared by a facile impregnation method and was successfully applied in the direct synthesis of ethanol from syngas. The results demonstrated that the distribution of CuO, CuAl2O4, and CuAlO2 in KCA‐xCu‐T catalysts can be effectively tuned by varying the calcination temperature (T/°C) and CuO loading (xCu/wt%). The cooperative effect between Cu0 and CuAlO2(Cu+) was proved to be responsible for the enhanced ethanol selectivity. Furthermore, the formation of CuAlO2 could efficiently fix Cu+ species in KCA‐10Cu‐900 sample, and thus lead to excellent catalytic stability (300 h at 400 °C). CuAl2O4 itself has no catalytic effect but can be gradually decomposed into Cu+ and/or Cu0 species during reaction, which further influenced the ethanol selectivity (38.4 wt%). [ABSTRACT FROM AUTHOR]

Jet fuel is not easy to synthesize by the biomass-to-liquid (BTL) process owing to the limitation of the Anderson-Schulz-Flory (ASF) hydrocarbon distribution law in Fischer-Tropsch synthesis (FTS) with biomass-derived syngas (CO+H2). Here, we realized an anti-ASF distribution to selectively produce jet fuel from biomass on a large scale by addition of small amounts of 1-olefin, a FTS product, into syngas, enhancing jet fuel selectivity in hydrocarbons up to 64% and that in oil product to as high as 91%. The Co/SiO2 catalyst (300 g) was loaded into a flow-type three-phase reactor and 120h continuous operation was conducted by using the real-time on-line biomass- derived syngas from an entrained bed gasifier of biomass (240 kgday-1) of Mitsubishi Heavy Industries, Ltd. The production rate of liquid oil reached 720 gkgcat -1h-1. The structure of the fresh and used catalyst was characterized in detail, accompanied with lab-scale data on reaction performance and catalyst properties. The stable technology process from biomass gasification to FTS, stable catalyst structure, and novel design of 1-olefin addition are the key to success in selectively converting biomass to jet fuel on a large scale. [ABSTRACT FROM AUTHOR]

Heteroatom doping is a promising approach to improve the properties of carbon materials for customized applications. Herein, a series of Cu catalysts supported on boron-doped carbon nanotubes (Cu/ xB-CNTs) were prepared for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The structure and chemical properties of boron-doped catalysts were characterized by XRD, TEM, N2O pulse adsorption, CO chemisorption, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption, which revealed that doping boron into CNT supports improved the Cu dispersion, strengthened the interaction of Cu species with the CNT support, introduced more surface acid sites, and increased the surface area of Cu0 and especially Cu+ sites. Consequently, the catalytic activity and stability of the catalysts were greatly enhanced by boron doping. 100 % DMO conversion and 78.1 % ethanol selectivity could be achieved over the Cu/1B-CNTs catalyst, the ethanol selectivity of which was almost 1.7 times higher than that of the catalyst without boron doping. These results suggest that doping CNTs with boron is an efficient approach to improve the catalytic performance of CNT-based catalysts for hydrogenation of DMO. The boron-doped CNT-based catalyst with improved ethanol selectivity and catalytic stability will be helpful in the development of efficient Cu catalysts supported on non-silica materials for selective hydrogenation of DMO to ethanol. [ABSTRACT FROM AUTHOR]

An autoreduced catalyst that comprised Cu nanoparticles encapsulated inside the nanochannels of carbon nanotubes (Cu@CNTs) was designed and prepared. As a result of the interaction of Cu species with the electron-deficient interior surface of the CNTs, calcination could realize the autoreduction of copper oxide directly with CNTs as the reductant. In the hydrogenation of dimethyl oxalate (DMO), the autoreduced Cu@CNTs catalyst, which did not need to be prereduced, exhibited an excellent catalytic activity, high target product selectivity, and high catalytic efficiency. Furthermore, the effect of the calcination temperature on the autoreduction degree of Cu@CNTs and the product selectivity in DMO hydrogenation were investigated in detail. The results showed that the autoreduction degree could be tuned easily by changing the calcination temperature, and the highest selectivity of ethanol could be obtained over the catalyst calcined at 500 °C. The findings obtained will inspire the development of other autoreduced catalysts, the reduction degree and catalytic performance of which can be tuned as desired. [ABSTRACT FROM AUTHOR]

A hierarchical meso/macroporous zeolite-supported Co catalyst (Co/ASB) was designed and employed for the direct synthesis of isoparaffins. The hierarchical porous zeolite (ASB) was developed by a steam-assisted crystallization method using alumina-modified meso/macroporous silica as the precursor. Structural characterization indicated that the as-synthesized ASB exhibited nanosized β-zeolite crystallites and a hierarchical meso/macroporous structure. The activity of the Co/ASB catalyst was much higher than that of conventional Co catalysts supported on SiO2 (Co/SiO2) and H-β-zeolite (Co/B). A high isoparaffins selectivity of 30.5 % was obtained from Co/ASB because of the hydrocracking/isomerization of long-chain hydrocarbons at the strong acidic sites of the β-zeolite. Furthermore, as a result of the fast diffusion of syngas in the unique hierarchical pores, the methane selectivity of Co/ASB was lower than that of Co/B. [ABSTRACT FROM AUTHOR]

Fused iron (FI), is a general Fischer-Tropsch synthesis (FTS) catalyst and can be used to convert syngas (CO+H2) into normal hydrocarbons. The syntheses of HZSM-5 or H-β zeolite-shell encapsulated catalysts for FTS have been reported previously, however, conventional zeolite-shell synthesis generally employs an organic template, which is neither economic nor environmentally benign. Here we report the synthesis, without using an organic template, of a millimeter-sized defect-free capsule catalyst covered by a MOR zeolite shell (thickness of 23 μm) on FI pellets. The capsule catalyst (HMOR/FI) exhibited excellent performance for FTS, greatly increasing the selectivity of middle isoparaffins. Compared with the pure FI catalyst, the CO conversion of the HMOR/FI capsule catalyst increased remarkably and the iso/ n ratio was almost 8 times that of the pure FI catalyst. This report provides an effective route to synthesize a capsule catalyst, which can reduce costs effectively and is also more environmentally benign than the current conventional zeolite-shell synthesis. [ABSTRACT FROM AUTHOR]

Front Cover: Propane Aromatization Tuned by Tailoring Cr Modified Ga/ZSM-5 Catalysts (ChemCatChem 16/2021) This picture means that propane is rapidly converted into propene and hydrogen on Ga and Cr modified ZSM-5 zeolite, and then converted into BTX aromatics. Keywords: BTX; Cr3+ species; Dehydrogenation; Impregnation sequence; Aromatization EN BTX Cr3+ species Dehydrogenation Impregnation sequence Aromatization 3545 3545 1 08/23/21 20210820 NES 210820 B The Front Cover b shows a symbolic rocket. [Extracted from the article]