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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]

Solar‐driven conversion of renewable biomass resources into high‐density hydrocarbon fuels can effectively realize biomass valorization and renewable energy conversion. In this work, an efficient self‐sensitized [2 + 2] photocycloaddition process is explored to develop highly strained fuel with high yield using norbornene and biomass‐derived cyclohexenone as feedstocks. The enhancement mechanism is revealed by phosphorescent measurement and theoretical calculation, and a reasonable reaction path for self‐sensitized [2 + 2] co‐cycloaddition is proposed. When using methanol as solvent, the apparent activation energy of co‐cycloaddition is 21.37 W/mol, which is lower than that of self‐cycloaddition (31.57 W/mol). Importantly, the jet‐fuel‐range highly strained fuel has high density (0.986 g/cm3) and high volumetric net heat of combustion (41.14 MJ/L), which are 5.34% and 4.39% higher than those of JP‐10, respectively. This work proposes a green and effective pathway for the preparation of high‐performance hydrocarbon fuel with polycyclic‐asymmetric structure. [ABSTRACT FROM AUTHOR]

Abnormal activation of the oncogene YAP in the Hippo pathway is a major feature in liver cancer and inactivation of MST1/2 has been shown to be responsible for the overactivation of YAP that led to tumorigenesis. However, mechanisms underlying MST1/2 dysregulation remain poorly understood. RNA‐seq analysis and genome (KEGG) pathway enrichment analysis were used to identify genes and pathways that were regulated by SIRT7. qRT‐PCR, ChIP, and luciferase assay were used to investigate transcriptional regulation. Mass spectrometry, co‐immunoprecipitation and immunoprecipitation were used to exam protein–protein interaction and post‐transcriptional modification. A xenograft mouse model was used to confirm the effect of SIRT7 and SIRT7 inhibitors on hepatocellular carcinoma (HCC) proliferation in vivo. We found that SIRT7 suppresses MST1 by both transcriptional regulation and post‐transcriptional modification, which in turn promotes YAP nuclear localization and transcriptional activation in liver cancer. Mechanistically, we revealed that SIRT7 suppresses MST1 transcription by binding to the MST1 promoter and inducing H3K18 deacetylation in its promoter region. In addition, SIRT7 directly binds to and deacetylates MST1, which primes acetylation‐dependent MST1 ubiquitination and protein degradation. In clinical samples, we confirmed a negative correlation between SIRT7 and MST1 protein levels, and high SIRT7 expression correlated with elevated YAP expression and nuclear localization. In addition, SIRT7 specific inhibitor 2800Z sufficiently inhibited HCC growth by disrupting the SIRT7/MST1/YAP axis. Our data thus revealed the previously undescribed function of SIRT7 in regulating the Hippo pathway in HCC and further proved that targeting SIRT7 might provide novel therapeutic options for the treatment of liver cancer. [ABSTRACT FROM AUTHOR]

Lignin is the main component of lignocellulose and the largest source of aromatic substances on the earth. Biofuel and bio‐chemicals derived from lignin can reduce the use of petroleum products. Current advances in lignin catalysis conversion have facilitated many of progress, but understanding the principles of catalyst design is critical to moving the field forward. In this review, the factors affecting the catalysts (including the type of active metal, metal particle size, acidity, pore size, the nature of the oxide supports, and the synergistic effect of the metals) are systematically reviewed based on the three most commonly used supports (carbon, oxides, and zeolites) in lignin hydrogenolysis. The catalytic performance (selectivity and yield of products) is evaluated, and the emerging catalytic mechanisms are introduced to better understand the catalyst design guidelines. Finally, based on the progress of existing studies, future directions for catalyst design in the field of lignin depolymerization are proposed. [ABSTRACT FROM AUTHOR]

Cyclopropane derivates are appealing to synthesis of high‐energy‐density fuels because of the high strained energy of the three‐numbered ring. The catalytic cyclopropanation of olefin with diazomethane is very effective to construct the carbocycle. The majority of the catalysts employed are nonrecyclable homogeneous compounds. Herein, we report cyclopropanation of polycyclic olefins catalyzed by heterogeneous Pd/C. The optimal cyclopropanation conditions were explored utilizing dicyclopentadiene as model substrate and a series of polycyclic olefins were cyclopropanated with high yield. Additionally, the catalyst has good recyclability and stability, as shown by characterizations as well as the fact that no inactivation happens after cyclopropanation. The synthesized cyclopropane derivates exhibit good fuel characteristics like high density (1.006–1.087 g/cm3), high volumetric net heat of combustion (42.58–46.45 kJ/cm3), good low‐temperature and combustion performance. This work shows industrial potential for cyclopropanation of polycyclic olefins with diazomethane. [ABSTRACT FROM AUTHOR]

The conversion of biomass is a favorable alternative to the fossil energy route to solve the energy crisis and environmental pollution. As one of the most versatile platform compounds, 5‐hydroxymethylfural (HMF) can be transformed to various value‐added chemicals via electrolysis combining with renewable energy. Here, the recent advances in electrochemical oxidation of HMF, from reaction mechanism to reactor design are reviewed. First, the reaction mechanism and pathway are summarized systematically. Second, the parameters easy to be ignored are emphasized and discussed. Then, the electrocatalysts are reviewed comprehensively for different products and the reactors are introduced. Finally, future efforts on exploring reaction mechanism, electrocatalysts, and reactor are prospected. This review provides a deeper understanding of mechanism for electrochemical oxidation of HMF, the design of electrocatalyst and reactor, which is expected to promote the economical and efficient electrochemical conversion of biomass for industrial applications. [ABSTRACT FROM AUTHOR]

The Haber–Bosch process for industrial NH3 production is energy‐intensive with heavy CO2 emissions. Electrochemical N2 reduction reaction (NRR) is an attractive carbon‐neutral alternative for NH3 synthesis, while the challenge associated with N2 activation highlights the demand for efficient electrocatalysts. Herein, we demonstrate that PdCu nanoparticles with different Pd/Cu ratios anchored on boron nanosheet (PdCu/B) behave as efficient NRR electrocatalysts toward NH3 synthesis. Theoretical and experimental results confirm that the highly efficient NH3 synthesis can be achieved by regulating the charge transfer between interfaces and forming a symmetry‐breaking site, which not only alleviates the hydrogen evolution but also changes the adsorption configuration of N2 and thus optimizes the reaction pathway of NRR over the separated Pd sites. Compared with monometallic Pd/B and Cu/B, the PdCu/B with the optimized Pd/Cu ratio of 1 exhibits superior activity and selectivity for NH3 synthesis. This study provides new insight into developing efficient catalysts for small energy molecule catalytic conversion via regulating the charge transfer between interfaces and constructing symmetry‐breaking sites. [ABSTRACT FROM AUTHOR]

Photocatalysis can create a green way to produce clean energy resources, degrade pollutants and achieve carbon neutrality, making the construction of efficient photocatalysts significant in solving environmental issues. Conjugated polymers (CPs) with adjustable band structures have superior light‐absorption capacity and flexible morphology that facilitate contact with other components to form advanced heterojunctions. Interface engineering can strengthen the interfacial contact between the components and further enlarge the interfacial contact area, enhance light absorption, accelerate charge transfer and improve the reusability of the composites. In order to throw some new light on heterojunction interface regulation at a molecular level, herein we summarize CP‐based composites with improved photocatalytic performance according to the types of interactions (covalent bonding, hydrogen bonding, electrostatic interactions, π‐π stacking, and other polar interactions) between the components and introduce the corresponding interface building methods, identifying techniques. Then the roles of interfaces in different photocatalytic applications are discussed. Finally, we sum up the existing problems in interface engineering of CP‐based composites and look forward to the possible solutions. [ABSTRACT FROM AUTHOR]

Steam methane reforming (SMR) is the most mature technology for hydrogen production in industry, and alumina supported nickel (Ni/Al2O3) is the most widely used catalyst. Herein, the key role of Ni valence state on the catalytic SMR performance of Ni/Al2O3 is reported. The ratio of Ni0/Ni2+ on Ni/Al2O3 is individually and effectively tuned by changing the reduction temperature after wet impregnation. Catalytic performance of Ni/Al2O3 is greatly dependent on the surface concentration of Ni0 and Ni2+. The catalyst reduced at 675 °C possesses balanced Ni0 and Ni2+ sites and exhibits superior catalytic performance, on which 60 % of methane is stably converted at 600 °C. CH4‐TPD and CO‐TPD profiles demonstrate that appropriate Ni0/Ni2+ ratio can promote the adsorption of CH4 and inhibit the moderate‐strength adsorption of CO, which leads to increased SMR activity and selectivity. [ABSTRACT FROM AUTHOR]

The excessive dependence on fossil fuels contributes to the majority of CO2 emissions, influencing on the climate change. One promising alternative to fossil fuels is green hydrogen, which can be produced through water electrolysis from renewable electricity. However, the variety and complexity of hydrogen evolution electrocatalysts currently studied increases the difficulty in the integration of catalytic theory, catalyst design and preparation, and characterization methods. Herein, this review first highlights design principles for hydrogen evolution reaction (HER) electrocatalysts, presenting the thermodynamics, kinetics, and related electronic and structural descriptors for HER. Second, the reasonable design, preparation, mechanistic understanding, and performance enhancement of electrocatalysts are deeply discussed based on intrinsic and extrinsic effects. Third, recent advancements in the electrocatalytic water splitting technology are further discussed briefly. Finally, the challenges and perspectives of the development of highly efficient hydrogen evolution electrocatalysts for water splitting are proposed. [ABSTRACT FROM AUTHOR]

A series of catalysts containing Pt or Pd nanoparticles (NPs) jointly regulated by cytidine (Cs) and polyvinylpyrrolidone (PVP) have been prepared for selective hydrogenation of cinnamaldehyde (CAL). The Pt/Pd NPs were supported on carbon nanotubes (CNTs) with different structures for promoting catalytic activity and tuning product selectivity. The synergistic effect of Cs and PVP on Pt/Pd surface promotes hydrogenation activity. The synergy between Pd NPs and multi‐walled CNTs with the diameter of <8 nm greatly promoted the hydrogenation of C=C bond in CAL. The synergy between Pt NPs and single‐walled CNTs with the diameter of <2 nm effectively enhanced the hydrogenation of C=O bond in CAL. These synergistic effects are attributed to the suitable size and exposed (111) facets of metal NPs, the transfer of electrons and the interaction between metal and support. [ABSTRACT FROM AUTHOR]

Proton exchange membrane water electrolyzer (PEMWE) technology is of interest in the context of electrocatalytic hydrogen generation from renewable energies. It has the benefits of immediate response, higher proton conductivity, lower ohmic losses, and gas crossover rate. One key step toward to large‐scale application, is the development of highly efficient, durable, and compatible anodic oxygen evolution electrocatalysts in acidic media to decrease the usage of expensive and scarce precious metals. Within this scenario, an in‐depth understanding of oxygen evolution reaction mechanisms including the adsorption evolution mechanism and lattice oxygen evolution mechanism is first provided to aid development of innovative materials and elucidate the origin of catalyst degradation. Second, recent progress in the development of oxygen evolution electrocatalysts in acid media is reviewed with an emphasis on the underlying structure–performance relationships. Third, the current application status and research progress in PEMWEs along with representative examples are discussed. Last, the remaining challenges and promising insights are proposed to inspire future studies on the development of hydrogen production technology from renewable energy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Non‐oxidative ethane dehydrogenation is a promising route to produce ethene. Herein, PtSn supported catalysts were investigated to achieve better ethane dehydrogenation performance by introduction of different Zr promoters, i.e., framework Zr and ZrO2, to mesoporous MCM‐41. In‐situ XRD, TEM and CO chemisorption show that aggregation of metal particles and phase segregation of Pt3Sn to Pt and PtSn3 at high temperature occur for PtSn/M, leading to bad ethane dehydrogenation activity. Strong interaction between ZrO2 and PtSn species, as proved by XPS, results in restrained metal particles, which promotes the initial reactivity. However, Pt phase generated on surface is disadvantageous for the desorption of produced ethene as indicated by CO‐IR and C3H6‐TPD, and pyridine‐IR and NH3‐TPD indicate strong acidity generated. Both deactivate the catalyst rapidly by deep dehydrogenation and coking. Moderate interaction between PtSn species and Si‐O‐Zr with much weaker acidity is formed when framework Zr is incorporated into MCM‐41, which benefits the dispersion of metal particles, formation of Pt3Sn/Pt species and stabilization of metal species from phase segregation. Outstanding initial ethane conversion and ethene selectivity of ca. 99% were achieved for the optimal PtSn/ZrM, which is more coking‐tolerant and stable by generating graphitic carbon mainly on support instead of active metals. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogenation provides an effective alternative way for the synthesis of industrial chemicals to meet the economic and environment expectations. Especially, over the past few years, metal‐organic frameworks (MOFs), featured with tunable structure, porosity, and crystallinity, have been significantly developed as many high‐performance catalysts in the field of photocatalysis. In this review, the background and development of photocatalytic hydrogenation are systemically summarized. In particular, the comparison between photocatalysis and thermal catalysis, and the fundamental understanding of photohydrogenation, including reaction pathways, reducing species, regulation of selectivity, and critical parameters of light, are proposed. Moreover, this review highlights the advantages of MOFs‐based photocatalysts in the area of photohydrogenation. Typical effective strategies for modifying MOFs‐based composites to produce their advantages are concluded. The recent progress in the application of various types of MOFs‐based photocatalysts for photohydrogenation of unsaturated organic chemicals and carbon dioxide (CO2) is summarized and discussed in detail. Finally, a brief conclusion and personal perspective on current challenges and future developments of photocatalytic hydrogenation processes and MOFs‐based photocatalysts are also highlighted. [ABSTRACT FROM AUTHOR]

Improving the insufficient carrier separation dynamics is still of significance in carbon nitride (C3N4) research. Extensive research has been devoted to improving the carrier separation efficiency through a single strategy, while ignoring the synergistic enhancement effect produced by coupling two or more conventional strategies. Herein, we reported the fabrication of cyano group‐containing Fe‐doped C3N4 porous materials via direct co‐calcination of iron acetylacetonate and melamine for synergistically improving the photocatalytic performance. Iron acetylacetonate can promote the generation of cyano groups and form Fe‐doping in C3N4, thereby increasing the visible‐light absorption and reactive sites. Further, the internal donor‐acceptor system formed by cyano groups and Fe‐doped sites promoted charge carrier separation and inhibited the radiation recombination of e−‐h+ pairs. The optimized photocatalytic activity of Fe−CN‐2 sample was 4.5 times of bulk C3N4 (BCN). [ABSTRACT FROM AUTHOR]

Propane dehydrogenation (PDH) is one of the most effective methods to produce propylene. But the industrial Pt‐based catalysts often suffer from short‐term stability under the high temperature reaction environment (500–700°C) via sintering and coke deposition. Herein, stable PDH reaction in high propylene yield has been achieved by the confinement of Pt–Zn intermetallic alloys (IMAs) in the channels of silicalite‐1. Single‐site Zn in the MFI framework was found to play a key role on assisting and stabilizing the PtZn IMAs for efficient PDH. By the cooperative action of the spatial confined PtZn IMAs and the lattice confined framework Zn, high propylene selectivity (>99%) without obvious deactivation was realized on the as‐developed catalyst (PtZn@S‐1) under 600°C even after 90 h. The low deactivation constant (0.003 h−1) was 6 times lower than that of the industrial PtSn catalyst. [ABSTRACT FROM AUTHOR]

Deep hydrogenation saturation of polycyclic aromatic hydrocarbons is of great importance for the production of valuable chemical products, but is hard due to the presence of hardly broken π bond. In this work, micro‐mesoporous HY supported Pd catalysts (Pd/HY‐a) have been prepared by a simple impregnation method following alkali treatment of pristine HY zeolite, which exhibited superior performance for the deep hydrogenation saturation of naphthalene. Pd/HY‐a was systematically characterized and compared with the Pd catalysts supported on pristine HY, ZSM‐5, SBA‐15, and Al2O3. In Pd/HY‐a, abundant mesoporous pore channels together with suitable B acid sites greatly facilitate the adsorption of the reactants (naphthalene and tetralin) and properly tune the electron state of loaded Pd. Therefore, efficient deep hydrogenation saturation of naphthalene has been achieved on Pd/HY‐a. Moreover, the kinetic behaviors of naphthalene hydrogenation on Pd/HY‐a were preliminarily investigated, in which the first‐order kinetic model fitted the experimental data well in the early reaction stage. [ABSTRACT FROM AUTHOR]

Energetic materials are widely used in the fields of military, civil engineering, and space exploration. The discovery of new energetic materials is essential to develop next‐generation technologies of weapon, mining, construction, and rocket propelling. In this study, a machine‐learning‐assisted method is developed for accelerating the discovery of new energetic materials via efficient prediction and quick screening. Suitable neural networks are established for accurately predicting the detonation properties of various N‐containing molecules based on their structures, including density (ρ), detonation velocity (D), and detonation pressure (P). Then, the minimum database volume for high‐precision extended prediction is determined. A proof‐of‐concept study for discovering new energetic compounds using machine learning is carried out, and 31 new N‐containing molecules with outstanding detonation properties are discovered. It is expected that the development of next‐generation energetic materials is greatly accelerated by the application of this strategy assisted by machine learning. [ABSTRACT FROM AUTHOR]

The demand for high performance and safer fuels has led to an ever increasing interest on gelled fuels. Here we report the synthesis and characterization of gelled high‐density fuels with low‐molecular mass gellants (LMMGs). This LMMG is synthesized simply by one step reaction and shows excellent gelling ability with the critical gellant concentration less than 1 %. Scanning electron microscopy studies reveal that LMMGs self‐assemble into fibrous structures and create a 3D network structure by crosslink of these fibers, which constructs the basic network of gel. The basic physical and thermal properties of gelled fuels such as gel transition temperature (TG), density, centrifugal stability and heat of combustion were investigated. Thermal characterizations reveal that the gels are thermally reversible and the TG increases with the concentration of gellant. Physical stability determined by the ratio of gel‐liquid separation under high speed centrifugation shows that gelled quadricyclane (QC) and exo‐tetrahydrotricyclopentadiene (HDF−T1) exhibit good physical stability. Rheological measurements show that the gels are shear‐thinning and the viscosity increases with an increasing amount of gellant. The viscosity of gelled QC is the highest among four gelled fuels, followed by gelled HDF−T1. The strain sweep tests and frequency‐sweep tests show that gelled QC also has superior mechanical strength while the gelled kerosene (RP‐3) has the lowest strength. Gel with higher strength has a higher viscosity and better physical stability due to a more stable internal structure and stronger resistance to deformation. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide is a highly valuable chemical, and electrocatalytic oxygen reduction towards H2O2 offers an alternative method for safe on‐site applications. Generally, low‐cost hematite (α‐Fe2O3) is not recognized as an efficient electrocatalyst because of its inert nature, but it is herein reported that α‐Fe2O3 can be endowed with high catalytic activity and selectivity via the engineering of facets and oxygen vacancies. Density‐functional theory (DFT)calculations predict that the {001} facet is intrinsically selective for H2O2 production, and that oxygen vacancies can trigger the high activity, providing sites for O2 adsorption and protonation, stabilizing the *OOH intermediate, and preventing cleavage of the OO bond. The synthesized oxygen‐defective α‐Fe2O3 single crystals with exposed {001} facets achieve high selectivities for H2O2 of >90%, >88%, and >95% in weakly acidic, neutral, and alkaline electrolytes, respectively, and the H2O2 production rate reaches 454 mmol g−1cat h−1 at 0.1 V versus RHE under alkaline conditions. In an anion exchange membrane fuel cell, a maximum H2O2 production of 546.8 mmol L−1 with a high Faradaic efficiency of 80.5% is achieved. Thus, this work details a low‐cost catalyst feasible for H2O2 synthesis, and highlights the feasibility of theoretical catalyst design for practical applications. [ABSTRACT FROM AUTHOR]

Multimetallic nanocatalysts have attracted increasing attention for steam reforming owing to highly exposed active sites, but often suffering from severe sintering. Herein, we design subnanometric Ni‐Pt bimetal clusters (ca. 1.7 nm) encapsulated in Silicalite‐1 zeolite (2Ni0.5Pt@S‐1) through ligand‐stabilized method to prevent sintering by fixing the metal into microporous channels. In the steam reforming of n‐dodecane test, 2Ni0.5Pt@S‐1 gave an excellent activity and stability with a decrease of conversion only 4% at 600°C for 4 hr, which was about a quarter that of 2Ni0.5Pt/S‐1 synthesized by co‐impregnation method, ascribing to superior sinter‐resistance of encapsulation structure. Moreover, 2Ni0.5Pt@S‐1 exhibited a higher H2 selectivity up to 69.9% than that of 2Ni0.5Pt/S‐1 (64.4%), owing to suppressed methanation reaction based on subnanometric clusters. Shape‐selective steam reforming of n‐dodecane and ofm‐xylene was also observed, because of m‐xylene could hardly diffuse into the zeolite channels due to its bulky molecular size, further preventing potential deactivation by tars in reforming process. [ABSTRACT FROM AUTHOR]

Direct conversion of solar light into chemical energy by means of photocatalysis or photoelectrocatalysis is currently a point of focus for sustainable energy development and environmental remediation. However, its current efficiency is still far from satisfying, suffering especially from severe charge recombination. To solve this problem, the piezo‐phototronic effect has emerged as one of the most effective strategies for photo(electro)catalysis. Through the integration of piezoelectricity, photoexcitation, and semiconductor properties, the built‐in electric field by mechanical stimulation induced polarization can serve as a flexible autovalve to modulate the charge‐transfer pathway and facilitate carrier separation both in the bulk phase and at the surfaces of semiconductors. This review focuses on illustrating the trends and impacts of research based on piezo‐enhanced photocatalytic reactions. The fundamental mechanisms of piezo‐phototronics modulated band bending and charge migration are highlighted. Through comparing and classifying different categories of piezo‐photocatalysts (like the typical ZnO, MoS2, and BaTiO3), the recent advances in polarization‐promoted photo(electro)catalytic processes involving water splitting and pollutant degradation are overviewed. Meanwhile the optimization methods to promote their catalytic activities are described. Finally, the outlook for future development of polarization‐enhanced strategies is presented. [ABSTRACT FROM AUTHOR]

The influences of impurities and oxidation evolution of waste cooking oil on the preparation of bio‐jet fuel via hydroconversion were studied. The hydrogenation active sites and acid sites were covered by heavy metals, sulfides, and basic nitrogen compounds, resulting in the increase of selectivity for bio‐jet fuel by decreasing the selectivity of diesel, aromatics, and iso‐alkanes. The effects of impurities, oxidation on the reaction pathway, and product distribution became more distinct with higher catalyst acidity. The evolution and variation of naphthalene, indan, and phenanthrene obtained from cyclic fatty acids influenced the properties of fuel or evoked the catalyst deactivation. This work will help to design new catalysts for selective conversion of waste cooking oil into bio‐jet fuel. [ABSTRACT FROM AUTHOR]

Electrochemical valorization of non‐food biomass‐derived carboxylates into fuels is promising for the conversion, storage, and distribution of renewable electricity. Herein, we demonstrate that biofuels, hydrogen, and bicarbonate can be simultaneously produced in an electrochemical cell by one‐step electrolysis of free fatty acids under ambient conditions on 3D self‐supported ultralow Pt loading (2 wt %) electrode. The three valuable products can naturally separate from each other during the electrolysis in the alkaline aqueous solution. The experimental suggests that Pt(100) and Pt(110) are favorable for the production of non‐Kolbe and Kolbe hydrocarbons, respectively. DFT calculation further clarifies the adsorption and stabilization of the reaction intermediates on Pt(100) and Pt(110). [ABSTRACT FROM AUTHOR]

As a new class of metal–nitrogen–carbon (M−N−C) material with 3 D microstructure, zeolitic imidazolate frameworks (ZIFs) are used to synthesize highly active electrocatalysts for the oxygen reduction reaction, as substitutes for commercial Pt/C in anion exchange membrane fuel cells. However, to form an effective catalyst layer (CL), the relationship between the microstructure of the ZIF‐derived catalyst and the fuel cell performance must be investigated. In this work, a hierarchically porous CL based on the carbon black (CB)‐controlled synthesis of a Co‐based ZIF (denoted as ZIF‐CB‐700) is constructed to optimize the triple‐phase boundary (TPB) and mass transfer. The power density at 40 °C of ZIF‐CB‐700 (95.4 mW cm−2) as cathode catalyst is about 4 times higher than that of the catalyst synthesized in the absence of CB and is comparable to that of the commercial 60 % Pt/C catalyst (112.0 mW cm−2). Both online and offline measurements suggest that the morphology and microstructure of the CL is crucial to form an active TPB region, dominating the fuel cell performance rather than only the high catalyst activity. [ABSTRACT FROM AUTHOR]

Fe‐doped transition metal (oxy)hydroxides are regarded as the most efficient oxygen evolution reaction (OER) electrocatalysts in alkaline conditions. The incorporation of Fe effectively enhances the OER activity of Co‐/Ni‐based materials, but the corresponding role of Fe in Co‐based (oxy)hydroxide materials still remains unresolved. Herein, α‐Co1−mFem(OH)x is synthesized and systematically engineered to study the effect of Fe content on the morphology, crystalline structure, electronic structure, and OER activity. As the Fe content is changed, the basic crystalline phase of α‐Co1−mFem(OH)x is consistent whereas the micromorphology changes. Much smaller and thinner nanoplates with more edge/defect sites are fabricated because of increased Fe incorporation. When the Fe content is more than 0.1, twin nanoparticles emerge at the edge/defect sites of the sister nanoplate. Additionally, the OER activity of α‐Co1−mFem(OH)x against Fe content can be plotted as a volcano curve. These data thus support a hypothesis that the edge/defect sites in α‐Co1−mFem(OH)x are responsible for the OER performance. The incorporation of Fe leads to not only the accelerated intrinsic reactivity of each active site, which is attributed to the strong electronic interaction between Co and Fe but also changes the number of edge/defect sites. [ABSTRACT FROM AUTHOR]

Developing efficient electrocatalysts from the earth‐abundant transition‐metal family is a great challenge for overall water splitting. Herein, we developed an approach to regulate the morphology and electronic structure of α‐Co0.9Fe0.1(OH)x nanoplates, in which FeCl2 (as a precursor) plays a significant role under reflux conditions. The resulting 2D α‐Co0.9Fe0.1(OH)x nanoplates exhibit more accessible edge active sites and more high‐valence Co species to boost its intrinsic activity. Therefore, this electrocatalyst shows outstanding oxygen evolution reaction performance (with an overpotential of 225 mV at 10 mA cm−2 and a Tafel slope of 39 mV dec−1 and good stability) and excellent activity toward the hydrogen evolution reaction (with an overpotential of 122 mV at 10 mA cm−2) in 1M KOH solution. When employed as bifunctional electrocatalysts on both the anode and cathode for overall water splitting, α‐Co0.9Fe0.1(OH)x can afford 10 mA cm−2 at 1.62 V with long‐term stability. The one‐pot synthesis of 2D Fe‐doped transition‐metal hydroxide nanoplates enriched with abundant edge sites may provide a new strategy for fabricating efficient overall water splitting catalysts. [ABSTRACT FROM AUTHOR]

Preparation of active and stable platinum nanoparticles (Pt NPs) for hydrogenation is of great importance. Herein, a joint experimental and theoretical study has been conducted to investigate the role of capping molecules on Pt NPs for hydrogenation. Both small biomolecules of adenine, D‐ribose, adenosine, and 2′‐deoxyadenosine and macromolecule of dextran have been studied as capping agents of Pt NPs. Kinetic data are collected and fitted for deep insight and clear comparison of Pt activity. TEM, SEM, XRD, nitrogen adsorption‐desorption were employed to characterize the obtained catalysts. DFT calculations have been carried out to investigate the exact interactions in this system. A volcano plot is obtained between the adsorption energy of 4‐NP on various Pt NPs against reaction rate constant (k), which is in accordance with the Brønsted‐Evans‐Polanyi (BEP) relation. Moreover, active and stable catalyst (Pt/rGO) has been prepared using dextran as capping agent and rGO as support. The hydrogenation of 4‐NP over Pt/rGO can reach 100% conversion in only 2 min. The catalyst can still maintain its activity after solvent removal and long‐time storage. Small biomolecules of adenine, D‐ribose, adenosine, and 2′‐deoxyadenosine and macromolecule of dextran have been studied as capping agents of Pt NPs. Kinetic data are collected and fitted for deep insight and clear comparison of Pt activity for hydrogenation. DFT calculations have also been carried out to investigate the exact interactions in this system. [ABSTRACT FROM AUTHOR]

Hollow nanospheres of Co/N−C composite have been synthesized using silica spheres with solid core and mesoporous shell (SCMS) as hard template and cobalt protoporphyrin as the precursor of C, N and Co by carbonization and etching. With the doping of only 0.68% Co into the hollow composite, activity and selectivity of ORR have been greatly facilitated. Moreover, hollow Co/N−C composite displays good electrochemical durability and tolerance to methanol crossover effect. The excellent catalytic performance of hollow Co/N−C nanospheres towards ORR can be ascribed to their unique hollow structure with mesopores, homogeneously distribution of Co nanoparticles, and suitable doping of N into carbon. Developing an efficient, easy‐to‐fabricate and applicable non‐precious metal catalyst for the oxygen reduction reaction (ORR) is extremely necessary for fuel cells. In this work, we developed Co‐N−C hollow sphere from solid core mesoporous shell (SCMS) silica spheres as hard template by porphyrin carbonization, to be used as oxygen reduction reaction (ORR) electrocatalyst. Co‐N−C hollow sphere displays better electrochemical durability and tolerance to methanol crossover effect in an alkaline medium than the 20 wt% Pt/C. [ABSTRACT FROM AUTHOR]

Abstract: Direct methanol fuel cells are promising renewable energy devices for automobiles and portable electronic devices. The development of high effciency, poison tolerance, long‐term stability, and noble metal‐free electrocatalysts for methanol oxidation is still a major challenge. Herein, we develop a noble metal‐free, 3D self‐supported, defect‐rich, hierarchical shell‐core structured Ni3S2 composite on Ni foam as electrocatalyst. This electrocatalyst shows a good activity, poison tolerance, and long‐term durability towards methanol oxidation in alkaline media. It shows the lowest onset potential (−340 mV vs. Hg/HgO) among all the Ni‐based catalysts reported up to date and a Pt‐level specific activity. The methanol oxidation peak current of the electrocatalyst retains more than 97.5 % even after 5,000 voltammetry cycles in 0.5 M KOH+1 M CH3OH. The morphology and composition of the electrocatalysts before and after stability test were characterized by SEM, TEM, XRD, and XPS. The high activity, poison tolerance, and stability are attributed to the binder‐free, directly grown Ni3S2 shell on the Ni foam backbone, the lattice defect sites, and the synergetic effects between the in‐situ formed active NiOx core and Ni3S2 shell during methanol oxidation. This work indicates that the self‐supported hierarchical shell‐core Ni3S2@Ni foam electrocatalyst is a viable alternative for commercial Pt‐based electrocatalyst applied in fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: To maximize the activity and durability of transition metal sulfides for water oxidation is still a great challenge. Herein, we developed a new cobalt phosphosulfide nanosheet on carbon fiber paper (CFP) substrate electrocatalyst (Co2−xSP/CFP) following a simple two‐step electrodeposition method. The cobalt sulfide nanosheets were first deposited onto CFP by cyclic voltammetry. Then, the surface structure and P/S ratio as well as the Co3+/Co2+ ratio of the phosphosulfide nanosheets were well tuned by regulating the cycling numbers of the phosphorous electrodeposition. Benefiting from the hierarchical structure, distinct phosphosulfide species, as well as a high Co3+ content derived from partial S substitution with P and nonstoichiometric phase, the as‐synthesized Co2−xSP/CFP exhibits remarkable activity with an overpotential of 279 mV at a current density of 10 mA cm−2, a low Tafel slope of 54 mV dec−1 and excellent long‐term stability towards OER (overpotential increase of only 4.7 % within 60 h). Structural analysis after stability test indicates that cobalt oxide/hydroxide species are formed on the surface, which contribute to the high performance and excellent durability for oxygen evolution. This provides a simple and facile approach to rationally design and synthesize transition metal phosphosulfides for advanced electrochemical application. [ABSTRACT FROM AUTHOR]

Significance: Nanosheet HZSM‐5 film vertically grown on the substrate with the tailorable macro‐ and meso‐pores between the layers of nanosheets is hydrothermally synthesized by seed‐assisted secondary growth method. The as‐prepared nanosheet HZSM‐5 film exhibits reaction rate enhancement up to 312% in catalytic cracking of n‐dodecane as well as twice light olefins selectivity, ascribed to the better mass transfer of reactants in the hierarchical porous structure and the ultra‐thin b‐axis pores of nanosheets. © 2018 American Institute of Chemical Engineers AIChE J, 64: 1923–1927, 2018 [ABSTRACT FROM AUTHOR]

Abstract: Transition‐metal chalcogenides have been widely investigated as a class of promising oxygen evolution reaction (OER) catalysts. But, they are still far from practical use because of moderate catalytic activity. Two‐dimensional (2D) materials with porous nanostructures are attractive for the efficient conversion of electrochemical energy. Herein, Co1‐xS novel porous microplates were synthesized through a facile self‐templated strategy based on the Kirkendall effect. By taking advantages of porous nanostructure and good catalytic properties of the hexagonal Co(OH)2 template, the unique Co1‐xS microplates provide higher efficient surface area and more accessible active sites. Moreover, the mass transfer and gas diffusion are also promoted, owing to the pores developed inside the microplates. As expected, the optimized porous Co1‐xS microplates demonstrate remarkable OER performance in alkaline electrolyte with an overpotential of 311 mV at 10 mA cm−2, a Tafel slope of 55 mV dec−1 and long‐term stability, which outperform the commercial IrO2 catalyst. The facile preparation, high catalytic activity, and excellent durability of the Co1‐xS porous hexagonal microplates show great promise in energy conversion applications. [ABSTRACT FROM AUTHOR]

Abstract: The direct conversion of waste cooking oil (WCO) into bio‐jet fuel was investigated over a core‐shell hierarchical USY@Al‐SBA‐15 zeolite‐supported NiMo catalyst. The core‐shell structure showed better acid and pore size distributions. The synergetic effect of the core‐shell micropore and mesopore structure significantly contributed to enhancing the selectivity for the jet fuel (C9–15 hydrocarbons) from 9.3 % over NiMo/USY up to 35.7 % over NiMo/USY@Al‐SBA‐15, with high isomerization (iso‐/n‐paraffins ratio = 2.7) and moderate aromatic fraction (18.7 %). The decarboxylation reaction was selectively enhanced. Optimal selectivity for jet fuel (39.7 %) was obtained at 380 °C and a high H2/oil ratio would decrease the yield of jet fuel. This catalyst showed excellent stability for the hydroconversion of WCO to hydrocarbons. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen evolution reaction (HER) in alkaline medium is currently a point of focus for sustainable development of hydrogen as an alternative clean fuel for various energy systems, but suffers from sluggish reaction kinetics due to additional water dissociation step. So, the state‐of‐the‐art catalysts performing well in acidic media lose considerable catalytic performance in alkaline media. This review summarizes the recent developments to overcome the kinetics issues of alkaline HER, synthesis of materials with modified morphologies, and electronic structures to tune the active sites and their applications as efficient catalysts for HER. It first explains the fundamentals and electrochemistry of HER and then outlines the requirements for an efficient and stable catalyst in alkaline medium. The challenges with alkaline HER and limitation with the electrocatalysts along with prospective solutions are then highlighted. It further describes the synthesis methods of advanced nanostructures based on carbon, noble, and inexpensive metals and their heterogeneous structures. These heterogeneous structures provide some ideal systems for analyzing the role of structure and synergy on alkaline HER catalysis. At the end, it provides the concluding remarks and future perspectives that can be helpful for tuning the catalysts active‐sites with improved electrochemical efficiencies in future. [ABSTRACT FROM AUTHOR]

We report carbon can be activated as metal-like hydrogenation catalyst for the selective hydrogenation of nitroarenes. Using DFT calculations we demonstrated the combination of P dopant and lattice defect in carbon can cause significant electron delocalization and change the band structure to a metal-like one, and thus both H2 and the nitro group are easily activated for selective hydrogenation. Then we fabricated this carbon catalyst with tunable concentration of P dopant and lattice defects by polymerization and carbonization of phytic acid, and found the concentration of lattice defect is closely related to that of P-dopants. The synthesized catalyst exhibits superior catalytic activity, perfect selectivity, and stability in the hydrogenation of nitroarenes, outperforming the reported metal-free, metal-oxide, and nickel catalysts. Importantly, the hydrogenation activity is linearly dependent on the P-doping and/or defect concentration, perfectly agreeing with the DFT calculation. This work is expected to provide a cheap way for large-scale production of anilines using metal-like carbon catalyst. [ABSTRACT FROM AUTHOR]

A coumarin-benzopyrylium ( CB) platform has been developed for the colorimetric and fluorogenic detection of bisulfite. The proposed probe utilizes coumarin as the fluorophore and positively charged benzopyrylium as the reaction site. The method employs the nucleophilic addition of bisulfite to the benzopyrylium moiety of CB to inactivate the electron-deficient oxonium ion. The driving force for photo-induced electron transfer is considerably diminished, thereby promoting the emission intensity of the coumarin fluorophore. The fluorescence intensity at 510 nm is linear with bisulfite concentration over a range of 0.2-7.5 μM with a detection limit of 42 nM (3δ). CB shows a rapid response (within 30 s) and high selectivity and sensitivity for bisulfite. Preliminary studies show that CB has great potential for bisulfite detection in real samples and in living cells. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) plays a key role in energy conversion and storage processes such as water splitting and carbon dioxide reduction. However, the sluggish kinetics caused by insufficient active surface and limited charge transfer hinder OER's wide applications. In this work, a novel self-templating strategy for the fabrication of composite CoO-MoO2 nanocages with enhanced OER performance is proposed. By designing a nanocage structure and incorporating conductive MoO2 to promote both mass and charge transfer, high OER activity (η = 312 mV at 10 mA cm−2) as well as good stability in the resulting CoO-MoO2 composite nanostructure can be achieved. This versatile synthetic strategy can also be extended to other metals (such as W) to provide greater opportunities for the controlled fabrication of mixed metal oxide nanostructures for electrochemical applications. [ABSTRACT FROM AUTHOR]

Hydroxyalkylation/alkylation of biomass-derived 2-methylfuran with cyclic ketones (cyclopentanone and cyclohexanone) has great potential in synthesizing high-density biofuel. But the conversion and selectivity are still unsatisfactory because the in-situ formed water decreases the acidity of catalyst and induces side reaction. Herein, hydrophobic mesoporous resins with sulfonic acid group (PS) and fluoride sulfonic acid group (PCS) were synthesized by a simple solvothermal reaction and ion exchange treatment, which have good mesoporous structure with surface area of 300-700 m2/g. Notably, PS and PCS have better hydrophobicity and oleophilicity as compared to widely used sulfonic acid functional amberlyst-15 and fluoride sulfonic acid functional nafion-212. In the hydroxyalkylation/alkylation reaction, PS shows higher activity and selectivity than amberlyst-15 while PCS surpasses nafion-212. Furthermore, both PS and PCS have good recycling stability in consecutive 5 runs. After hydrodeoxygenation, two high-density biofuels with density of 0.819 and 0.825 g/mL were obtained. © 2016 American Institute of Chemical Engineers AIChE J, 63: 680-688, 2017 [ABSTRACT FROM AUTHOR]

Conjugated polymers, covalent bonding, heterojunctions, interface engineering, noncovalent interactions Frontispiece: Interface Engineering of Conjugated Polymer-Based Composites for Photocatalysis Keywords: conjugated polymers; covalent bonding; heterojunctions; interface engineering; noncovalent interactions EN conjugated polymers covalent bonding heterojunctions interface engineering noncovalent interactions 1 1 1 12/29/22 20221227 NES 221227 B Interface engineering b can facilitate the self-assembly of conjugated polymer-based composites through a series of intermolecular interactions (covalent bonding, hydrogen bonding, dipole-dipole interactions, electrostatic interactions, and - stacking) between the components, further improving the photocatalysis process, which depends heavily on smooth charge transfer at the well-formed interface. [Extracted from the article]

The washcoats of the hierarchical HZSM-5 zeolite (through desilication) were prepared on the inner surface of SS304 stainless-steel tubes. The properties of slurries and coatings were characterized by analysis of particle size, measurements of rheological property, loading, adhesion, and finally the catalytic cracking test. It was found that introducing mesoporosity on the zeolite crystals was beneficial for reducing the particle size during ball milling for slurries preparation, which was helpful for improving loading due to a significant change in the rheological property. As the interaction between the particles with different sizes was enhanced after ball milling, the adhesion of the prepared coatings was improved. The catalytic activity and stability of the hierarchical HZSM-5 coatings for the catalytic cracking of n-dodecane were 56% and 75% higher than that of the conventional one, respectively. This probably resulted from the enhanced diffusion rate of reactant and products in the crystals and the coatings. [ABSTRACT FROM AUTHOR]

A novel structured catalyst of binderless micro-HZSM-5 zeolite coating was prepared on stainless-steeled tubes (i.d. 2 mm) through wash coating and vapor-phase transport (VPT) crystallization method. The subsequent crystallization of amorphous SiO2 binders improved the coatings adhesion tremendously by more than 10 times with the least amount of binders (<20% by weight), attributed to the remarkably enhanced interlock by the formed Mordenite Framework Inverted structure between zeolite particles. Catalytic cracking of supercritical n-dodecane (500°C, 4 MPa) was used to examine the catalytic performance of the coatings as prepared, indicating that MZC-V0.2 exhibited a catalytic activity improvement by 8% and a decreased deactivation rate by 48%. The improved catalytic performance may result from its high acid sites amount by incorporating extra-framework Al into HZSM-5 framework, and the possible depressing of pore-mouth deactivation through partial modification of surface acid sites during VPT treatment. This work provides a potential technique to prepare mechanically stable zeolite coatings with high catalytic activity but less binder usage. [ABSTRACT FROM AUTHOR]

Significance ZIF-8, a typical and popular type of MOFs, was synthesized and carbonized directly to produce highly porous carbon without washing or activation. The resulting carbon was found to be a promising candidate for adsorption desulfurization of DBT with a maximum adsorption capacity of 26.7 mgS/g in the concentration range below 174 ppmS, and the adsorption capacity decreased approximately 17% with the addition of 10% para-xylene. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2747-2751, 2014 [ABSTRACT FROM AUTHOR]

Significance Multilayer b-orientated HZSM-5 catalytic coating is controllably synthesized by repeated growth of zeolite layer on TiOH-modified surface of sublayer. The as-prepared zeolite coating shows performance enhancement up to 110% in catalytic cracking of n-dodecane ascribed to enhanced mass transfer in its straight and short pathway along the b-axis. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1964-1968, 2014 [ABSTRACT FROM AUTHOR]

A series of Al-incorporated mobile crystalline materials (Al-MCM-41) were prepared by hydrothermal synthesis and characterized by XRD, N2 adsorption (isotherms), inductively coupled plasma (ICP) analysis, 27Al magic angle spinning (MAS) NMR spectroscopy, and in situ pyridine adsorption (IR analysis). All samples exhibit an ordered structure with the majority of Al species in framework positions, except those with an SiO2/Al2O3 ratio ≤10. The concentration of acid sites is closely related to the Al content in the unit cell. In the presence of Al-MCM-41, both α- and β-pinenes are quickly transformed into isomerized products, which then couple to form homo- and heterodimers. Lewis acid sites are active in triggering both the isomerization and dimerization reactions, but weak Brønsted acid sites seem inactive for the dimerization. Al-MCM-41 has a greater activity than many other microporous and layered materials, and can be easily regenerated. The activity correlates well with the concentration of acid sites, and the sample with an SiO2/Al2O3 ratio of 20 shows the highest activity. [ABSTRACT FROM AUTHOR]