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van der Waals heterojunctions based on transition-metal dichalcogenides (TMDs) offer advanced strategies for manipulating light-emitting and light-harvesting behaviors. A crucial factor determining the light–material interaction is in the band alignment at the heterojunction interface, particularly the distinctions between type-I and type-II alignments. However, altering the band alignment from one type to another without changing the constituent materials is exceptionally difficult. Here, utilizing Bi2O2Se with a thickness-dependent band gap as a bottom layer, we present an innovative strategy for engineering interfacial band configurations in WS2/Bi2O2Se heterojunctions. In particular, we achieve tuning of the band alignment from type-I (Bi2O2Se straddling WS2) to type-II and finally to type-I (WS2straddling Bi2O2Se) by increasing the thickness of the Bi2O2Se bottom layer from monolayer to multilayer. We verified this band architecture conversion using steady-state and transient spectroscopy as well as density functional theory calculations. Using this material combination, we further design a sophisticated band architecture incorporating both type-I (WS2straddles Bi2O2Se, fluorescence-quenched) and type-I (Bi2SeO5straddles WS2, fluorescence-recovered) alignments in one sample through focused laser beam (FLB). By programming the FLB trajectory, we achieve a predesigned localized fluorescence micropattern on WS2without changing its intrinsic atomic structure. This effective band architecture design strategy represents a significant leap forward in harnessing the potential of TMD heterojunctions for multifunctional photonic applications.

• GNPs@Al 2 O 3 with undulating microstructure was used to optimize Cu matrix composite. • GNPs@Al 2 O 3 ameliorates mesoscopic internal structure and modifies the interaction. • Multi structure generates extra toughening effect by crack bridging and deflection. • Manipulating the skeleton of conductive pathways ameliorates the EC of composites. Tailoring structure is of giant significance in achieving a synergy between mechanical properties-electrical conductivity (EC) of Cu matrix composites. This work contributes an in-depth understanding of undulating graphene-Cu interface architecture optimizing multiscale structure in graphene/CuNb composites fabricated by in situ synthesis integrated with powder metallurgy process. It was elucidated that the undulating graphene-Cu interface not only evidently ameliorates mesoscopic internal structure, but also elaborately modifies the interaction between the added phase and matrix, leading to prominent contribution to the mechanical properties through effective structural regulation as well as modulating dislocation accumulation/storage and crack deflection. Meanwhile, manipulating the skeleton of conductive pathways enables ameliorating the EC of composites. These findings can unfold brand new frontiers for alleviating themechanical-functional characteristics conflict of Cu matrix composites. [Display omitted] [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide) (PEO)-based electrolytes have been extensively studied for all-solid-state lithium-metal batteries due to their excellent film-forming capabilities and low cost. However, the limited ionic conductivity and poor mechanical strength of the PEO-based electrolytes cannot prevent the growth of undesirable lithium dendrites, leading to the failure of batteries. Metal–organic frameworks (MOFs) are functional materials with a periodic porous structure that can improve the electrochemical performance of PEO-based electrolytes. However, the enhancement effect of MOFs with different metal centers and the interaction mechanism with PEO remain unclear. Herein, MOF-74s with Cu or Ni centers are prepared and used as fillers of PEO-based electrolytes. Adding 15 wt % of Cu-MOF-74 to the PEO-based electrolyte (15%Cu-MOF/P–Li) effectively improves the ionic conductivity, lithium transference number, and mechanical strength of the PEO-based electrolyte simultaneously. Furthermore, the ordered pore channels of Cu-MOF-74 provide uniform Li-ion transport pathways, facilitating homogeneous Li+deposition. As a result, the lithium symmetric cell with 15%Cu-MOF/P–Li shows stable cycles for 1080 h at 0.1 mA cm–2and 0.1 mAh cm–2, and the Li | 15% Cu-MOF/P–Li | LFP full cell exhibits a long cycle life up to 200 cycles at 60 °C and 0.5 C, with a capacity retention rate of 89.7%.

In order to improve the interface wettability as well as the interfacial bonding between graphene and copper matrix, in this work, graphene nanoplates modified with nickel nanoparticles (Ni-GNPs) were synthesized using a one-step method based on spray-drying and chemical vapor deposition. Thereafter, 0.33 wt% Ni-GNPs were introduced into copper matrix composite by the molecular-level mixing method, leading to further enhancement of 90% in yield strength. This is attributed to the presence of Ni-GNPs, which provided high resistance to matrix against deformation. In addition, with the modification of nickel at the interface, the wettability and interfacial bonding between graphene nanoplates and copper matrix were improved, which enhanced the load transfer then. Furthermore, the microstructures and strengthening mechanisms were investigated and discussed meanwhile.

Oxided-dispersion-strengthened (ODS) alloys are promising high-strength materials used in extreme environments such as high-temperature and radiation tolerance applications. Until now, ODS alloys have been developed for reducible metals by chemical processing methods, but there are no commercially available ODS alloys for unreducible metals, namely, Al, Mg, Ti, Zr and so on, owing to the challenge of uniformly dispersing oxide particles in these alloys by traditional techniques. Here we present a strategy to achieve ODS Al alloys containing highly dispersive 5 nm MgO nanoparticles by powder metallurgy, using nanoparticles that have in situ-grown graphene-like coatings and hence largely reduced surface energy. Notably, the densely dispersed MgO nanoparticles, which have a fully coherent relationship with an Al matrix, show effective suppression of interfacial vacancy diffusion, thus leading to unprecedented strength (~200 MPa) and creep resistance at temperatures as high as 500 °C. Our processing approach should enable the dispersion of ultrafine nanoparticles in a wide range of alloys for high-temperature-related applications.

• The "GNS-Cu/CuAl 2 -Al" interfacial structure enormously contributes to the effective load transfer, either by enhancing the GNS-Al adhesion or by elevating the interfacial slippage resistance. • A typically intragranular distribution of Cu@GNS in microstructure can remarkably enhances the work hardening of composite via dislocation strengthening. • The high corrosion resistance of the composite is rationalized on basis of the decreased number density of galvanic cells along grain boundaries affected by intragranular distribution of Cu@GNS. Al matrix composites generally possess high strength but sacrifice ductility and corrosion resistance resulting from the dense intergranular reinforcements. Herein, we report a solid-state reactive sintering pathway to construct an Al-Zn-Mg composite reinforced by intragranular Cu nanoparticles modified graphene nanosheets (Cu@GNS), which demonstrates both superior mechanical properties (∼630 MPa of tensile stress and ∼9.1% of fracture elongation) and exceptional corrosion resistance. It is shown that the "GNS-Cu/CuAl 2 -Al" interfacial structure greatly contributes to the load transfer, either by enhancing the GNS-Al adhesion or by elevating the interfacial slippage resistance in terms of the "drag effect" of hybrid particles. Meanwhile, the comprehensive characterization demonstrates that such intragranular Cu@GNS not only enhances the dislocation multiplication efficiency for work hardening but also contributes to the high corrosion resistance via decreasing the corrosion kinetics and suppressing the severely localized corrosion. This work provides a novel strategy for the exceptional mechanical-corrosion combination of composites by tailoring intragranular reinforcements. [ABSTRACT FROM AUTHOR]

• The delicate combined technique of ball milling and pressureless sintering route facilitates the formation of continuous AlN nanolayer. • The construct of the Al-AlN-BNNSs coherent transition interface improved the interfacial bonding strength of BNNSs/Al composites through covalent bonds. • The coherent transition interface significantly improves the strengthening efficiency of the reinforcement and load transfer efficiency. • The coherent transition interface contributes to toughening the composite during tensile deformation by delaying crack initiation and crack deflection. The deformation incompatibility of components is a bottleneck restricting the exaltation of the strength and ductility of composites. Herein, the coherent transition interface was designed and produced in hexagonal boron nitride nanosheets (BNNSs)/Al composites by reaction sintering route, expecting to relieve the deformation incompatibility between BNNSs and Al. It is demonstrated that with the sintering temperature for composites raising from 600 °C to 650 °C, 700 °C and 750 °C, different interface bonding characteristics, which involve nucleation and growth of AlN continuous nanolayer, were confirmed. Furthermore, first-principles calculations show that the generation of the coherent transition interface improved the interfacial bonding strength of BNNSs/Al composites through covalent bonds. The composites with coherent transition interface exhibit excellent strength-toughness combination in tensile and impact tests. The finite element simulation and in-situ approach under tensile tests were applied to investigate the influence of transition interface structure on deformation behavior of BNNSs/Al composite. It is found that the generation of the transition interface can not only weaken the stress partitioning behavior in the elastic stage, but also constrain the crack initiation and propagation behavior in the elastic-plastic stage and plastic stage, thereby improving the deformation compatibility between BNNSs and Al. The present work provides a novel view into the breakthrough for the trade-off relationship of strength and ductility by coherent transition interface design in nanocomposites. [ABSTRACT FROM AUTHOR]

Tea is a famous beverage that is produced from leaves of Camellia sinensis. Amongst the six major tea categories in China, dark tea is the only one that involves microbial fermentation in the manufacturing process, which contributes unique flavors and functions for the tea. In the recent decade, the reports about the biofunctions of dark teas have increased rapidly. Therefore it may be the proper time to consider dark tea as one potential homology of medicine and food. In this viewpoint, our current understanding of the chemical constituents, biological activities and possible health beneficial effects of dark teas were introduced. Some future directions and challenges to the development perspectives of dark teas were also discussed.

Incorporating reinforcements can improve the mechanical properties of Al matrix composites but make them susceptible to corrosion attacks by facilitating the formation of a galvanic cell network along the interface. The optimization of the interfacial structure improves the corrosion resistance of the composites. Herein, a solid-state thermite reaction integrated with a heat treatment strategy was developed to create plain interfaces, encompassing the grain boundary (GB) and reinforcement–matrix interface, in an Al–CuO composite system. The intergranular corrosion behavior and susceptibility to stress corrosion cracking of the composite were comprehensively examined by immersion/electrochemical corrosion tests and microstructural characterizations. The intragranular distribution of nanosized secondary phases, i.e., Al2O3and precipitates, was investigated to address their contribution to the continuous galvanic cell detachment along the GBs and interruption of the corrosion path, thus boosting the corrosion duration. In addition, the tightly bonded Al2O3–Al interface with low strain energy distinctly lowers local susceptibility to corrosion. This study illuminates the correlation between interface characteristics and corrosion mechanisms in the composites, which can shed light on the development of high-corrosion-resistant composites.

Food-medicine products are important materials for daily health management and are increasingly popular in the global healthy food market. However, because of the biocultural difference, food-medicine knowledge may differ among regions, which hinders the global sharing of such health strategies. Aim at bridging the food-medicine knowledge in the East and West, this study traced the historical roots of food and medicine continuum of the East and West, which was followed by a cross-cultural assessment on the importance of food-medicine products of China, thereafter, the current legislative terms for food-medicine products were studied using an international survey. The results show that the food and medicine continuum in the East and West have their historical roots in the traditional medicines since antiquity, and the food-medicine knowledge in the East and West differs substantially; although the food-medicine products have common properties, their legislative terms are diverse globally; with proofs of traditional uses and scientific evidence, food-medicine products are possible for cross-cultural communication. Finally, we recommend facilitating the cross-cultural communication of the food-medicine knowledge in the East and West, thus to make the best use of the traditional health wisdom in the globe.

The structural deterioration caused by the relatively weak out-of-plane bending stiffness and the chemically-active edge area of graphene limits its outperformance in strengthening for Al matrix composites (AMCs). Introducing one-dimensional (1D) carbon nanotubes (CNTs) to graphene/metal system is one of the promised strategies to complement the weakness of 2D graphene and make full use of the outstanding intrinsic properties of the both reinforcements. To date, such synergistic strengthening and toughening mechanisms are largely unknown. In this study, AMCs reinforced by a novel hybrid reinforcement, i.e., graphene nanosheets decorated with Cu nanoparticles and CNTs (Cu@GNS-CNTs), are fabricated by an in-situ synthesis method. The combined contrast experiments validated that the organically integrated reinforcing structure promotes the intrinsic load bearing capacity of GNS and the strain hardening capability of the Al matrix simultaneously. As a result, the composites achieved excellent tensile strength and uniform elongation with almost no loss. The strengthening mechanism originated primarily from the hybrid reinforcement exhibits superior load-transfer, fracture inhibition and dislocation storage capability by controlling the interface reaction to construct an effective interface structure without damaging the reinforcement. Our work identifies a promising structural modification strategy for 2D materials and provides mechanistic insights into the synergistic strengthening effect of graphene/CNTs hybrid reinforcement. [Display omitted] [ABSTRACT FROM AUTHOR]

The construction and application of traditional high-strength 7075 aluminum alloy (Al7075) through selective laser melting (SLM) are currently restricted by the serious hot cracking phenomenon. To address this critical issue, in this study, Si is employed to assist the SLM printing of high-strength Al7075. The laser energy density during SLM is optimized, and the effects of Si element on solidification path, relative density, microstructure and mechanical properties of Al7075 alloy are studied systematically. With the modified solidification path, laser energy density, and the dense microstructure with refined grain size and semi-continuous precipitates network at grain boundaries, which consists of fine Si, β-Mg2Si, Q-phase and θ-Al2Cu, the hot cracking phenomenon and mechanical properties are effectively improved. As a result, the tensile strength of the SLM-processed Si-modified Al7075 can reach 486 ± 3 MPa, with a high relative density of ~ 99.4%, a yield strength of 291 ± 8 MPa, fracture elongation of (6.4 ± 0.4)% and hardness of 162 ± 2 (HV0.2) at the laser energy density of 112.5 J/mm3. The main strengthening mechanism with Si modification is demonstrated to be the synergetic enhancement of grain refinement, solution strengthening, load transfer, and dislocation strengthening. This work will inspire more new design of high-strength alloys through SLM.

Improving dissociation and diffusion of lithium ions is the key to solving the practical application of polymer-based solid-state electrolytes (SSE). Here, a low-cost three-dimensional hydroxyapatite (HAP) nanowire is used in polyethene oxide to obtain an enhanced lithium-ion electrolyte. The oxygen-rich interface of HAP provides an integrated dissociation–diffusion platform for lithium salts. The TFSI–anions tend to coordinate with calcium ions, which makes it easier for lithium ions to escape and stay in a free state. The lateral nucleus in the HAP polyethene electrolyte regulates the diffusion from spherical diffusion into linear planar diffusion, which is confirmed by chronoamperometry curves and in situ observation. The stability of the electrolyte at high voltages is improved by inhibiting the superoxide radicals of polyethene oxide chains, which is demonstrated by nuclear magnetic resonance and electron paramagnetic resonance spectroscopy methods. The initial specific charge capacity of the Li/SPE/LiFePO4cell with HAP-modified polyethene oxide at 2 C is 148.8 mA h/g, and its initial Coulombic efficiency is 95.17%. After 100 cycles, the specific discharge capacity is 125.5 mA h/g with 99.91% retention per cycle. This oxygen-rich interface strategy would guide the discovery of novel materials for polymer-based SSE.

Interfaces play a key role in affecting the strengthening efficiency of metal matrix composites. Herein, boron nitride nanosheets (BNNSs)-AlN-Al transition interface featuring Mg segregation was designed, which contributes to the exceptional strengthening of BNNSs/Al–4Mg composite. Both experiments and theoretical calculations show that Mg solutes tend to segregate at the BNNS/Al interface. Such Mg segregation is revealed to enhance interface bonding and cohesion, which increases the load-transfer efficiency and hence contributes to the exceptional strength of composites. The transitional interface featuring AlN transitional nanolayer and Mg segregation is supposed to alleviate the stress concentration near the interface by mitigating the deformation incompatibility between BNNSs and Al matrix. It is considered that Mg segregation facilitates planar slip of dislocations which benefits strain/stress transfer and delocalization at the interface. Furthermore, the fracture morphologies suggest the BNNSs-AlN-Al transition interface can effectively blunt crack propagation and change crack propagation path, which notably contributes to the exceptional strength-ductility of BNNSs/Al–4Mg composite. The present work provides a new solution to design aluminum matrix composites with excellent mechanical properties through interfacial engineering.

• The 0.4 wt% GNSs/Al-Si composite foam sshow the energy absorption capacity of 6.8 ± 0.7 MJ/m3. • The graphene nanosheets could provide more pore nucleation sites and protect the liquid films. • The growth of Si precipitates was pronounced inhibited by the graphene nanosheets. The integrity and regularity of pore morphology play an important role in determining the mechanical properties of the metallic foam materials. The conventional methods on refining pore morphology are mainly focused on the optimization of fabrication techniques, however, they are usually inconvenient and complicated. Recently, incorporating nano reinforcement is considered to be a suitable way to fabricate metallic composite foams accompanied by optimized pore morphology and enhanced mechanical properties. In this work, through a facile and rapid powder metallurgy foaming method, the aluminum-silicon (Al-Si) alloy composite foams reinforced by graphene nanosheets (GNSs) are successfully fabricated. The microstructure analyses reveal that, for the Al-Si alloy foams incorporating the GNSs (GNSs/Al-Si composite foams), the pore size is transformed to be smaller, the pore size distributions become more homogeneous and the pore shape is also refined to a regular and roundish state. Meanwhile, the shape of Si precipitates is found transforming from an irregular long strip (length of ~20 μm, width of ~5 μm) to a fine particle state (diameter of ~5 μm). Moreover, the compressive testing results show that, the 0.4 wt% GNSs/Al-Si composite foams own the optimal compression stress of 11.7 ± 0.5 MPa, plateau stress of 10.0 ± 1.0 MPa and energy absorption capacity of 6.8 ± 0.7 MJ/m3, which have improvement of 58.1%, 53.8% and 51.1% in comparison with the Al-Si alloy foams counterpart, respectively. The present findings may pave a new way for developing new generation of metallic composite foams that with stable microstructure and excellent mechanical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

• GNPs/Al-Cu composite with obvious aging enhancement was fabricated by powder metallurgy. • The addition of GNPs could accelerate the formation of precipitates. • Comparing with the solution treated GNPs/Al-Cu composite, aging led to obvious increase in hardness but less enhancement in strength. Microstructural and mechanical behavior of heat treatable Al-4.6Cu binary alloy reinforced with graphene nanoplates (GNPs) in different heat treatment status were investigated in this paper. The addition of GNPs significantly enhanced the yield strength and tensile strength of Al-Cu alloy regardless of the heat-treatment conditions. It was also found that GNPs accelerated the formation of precipitates, leading to a greatly shortened aging time for GNPs/Al-4.6Cu composite to reach the peak hardness. However, aging treatment enhanced the strength of GNPs/Al-Cu composite very little, which could be explained by the interaction between GNPs, precipitates and dislocations. This work inspires us that the heat treatment process of aluminum alloy matrix composites should be designed independently with the matrix in quest of an optimum performance. [ABSTRACT FROM AUTHOR]

W atoms/clusters are employed to in situassist the development of layered vertically aligned carbon nanotube arrays (VACNTs) through hot-filament-assisted chemical vapor deposition (HFCVD) with liquid binary Fe3O4/AlOxcatalysts. The hot W filament was utilized to in situevaporate atomic W and form W clusters on Fe catalysts, which have a strong impact on the growth of layered VACNT arrays. The migration and Ostwald ripening of Fe catalysts are found to be suppressed immediately with more W clusters deposition during CNT growth. Through controlling the deposition of W clusters, the electrochemical energy storage performance of as-prepared layered VACNT arrays is also tunable as electrodes of ion-based supercapacitors. The layered VACNT arrays can achieve a high capacity of 83.1 mF cm–2and possess desirable rate performance due to the suitable hot filament condition (55 W for 90 s). This work provides a new perspective to in-depth understand the behavior of W filament during HFCVD and the significant role of the in situgenerated W clusters on the growth of CNTs by maintaining the catalytic activity and structure of catalysts.

The Sabatier principle instructs that WN catalysts containing an appropriate amount of N-vacancy for Li-CO2battery have moderate adsorption energy for intermediates and thus have high reversibility and catalytic stability for carbon dioxide reduction reaction (CO2RR) and carbon dioxide evolution reaction (CO2ER).

Graphene/metal oxide nanocomposites have been widely used as the anode materials for Li ion batteries, which exhibit much higher Li storage capacity beyond their theoretical capacity. In order to make clear the Li storage mechanism in graphene/metal oxide, we systematically investigated the interface and (B, N, O, S) doping effects on Li ion storage behavior in graphene/Li2O using first-principles total energy calculations. It is revealed that the doping elements increase the van der Waals interface interaction of graphene/Li2O by changing the electronic structure of graphene through different mechanisms. The Li storage at the graphene/Li2O interface exhibits the synergistic effect resulting from the enhanced interface interaction by the Li insertion at the interface. The p-type and n-type doping induced by B and N dopants in graphene enhance and reduce the Li storage capability of graphene/Li2O, respectively. O and S doping result in the localization of the electronic states in graphene which benefits the Li adsorption at the interface. The localization of electronic states combined with the appropriate dopant electronegativity can enhance the Li atoms adsorption and diffusion simultaneously. Thereby, the highest interfacial lithium storage (0.330 mhA/m2) is obtained for the O-doped system, while the S-doped system possesses the good balance between interfacial Li storage (0.220 mhA/m2) and diffusion energy barrier (0.27 eV). The results open a new insight for the design of graphene/metal oxide composites as energy storage materials.

A series of NiCo2P-based electrocatalysts, which were wrapped by CeO2whose oxygen vacancies (VO) are partially filled with phosphorus atoms (named as NiCo2Px/PxFVo-CeO2, where xrefers to the consumption of NaH2PO2·H2O), have been fabricated to improve the electrocatalytic reactivity of NiCo2P toward hydrogen evolution in alkaline solution. In the novel catalysts, the P atoms fill the oxygen vacancies, elevate the chemical valence state of Ni2+and Co3+, and increase the hydride acceptors, which reinforcing the promoting effect of CeO2in the hydrogen evolution reaction (HER). Moreover, the negatively charged P atoms capture the positively charged protons more easily, benefiting the Volmer step during HER. Furthermore, the synergistic effect between oxygen vacancies and the filled P atoms accelerates the migration rate of electrons/ions and increases the electrochemical active area. All of the above are advantageous to the hydrogen evolution of NiCo2Px/PxFVo-CeO2in alkaline electrolyte. As a result, the overpotential as low as 33.6 mV is achieved for NiCo2P0.3/P0.3FVo-CeO2in alkaline media to drive a current density of 10 mA cm–2. The reactivity is superior to that of Pt/C at a large current density along with a Tafel slope of 61.24 mV dec–1and long-term durability, which giving a new technology for efficient transition-metal catalyst candidates toward HER in alkaline solution.

Rhizosphere microorganisms, as one of the most important components of the soil microbiota and plant holobiont, play a key role in the medicinal plant-soil ecosystem, which are closely related to the growth, adaptability, nutrient absorption, stress tolerance and pathogen resistance of host plants. In recent years, with the wide application of molecular biology and omics technologies, the outcomes of rhizosphere microorganisms on the health, biomass production and secondary metabolite biosynthesis of medicinal plants have received extensive attention. However, whether or to what extent rhizosphere microorganisms can contribute to the construction of the quality evaluation system of Chinese medicinal materials is still elusive. Based on the significant role of rhizosphere microbes in the survival and quality formation of medicinal plants, this paper proposed a new concept of rhizosphere microbial markers (micro-markers), expounded the relevant research methods and ideas of applying the new concept, highlighted the importance of micro-markers in the quality evaluation and control system of traditional Chinese medicines (TCMs), and introduced the potential value in soil environmental assessment, plant pest control and quality assessment of TCMs. It provides reference for developing ecological planting of TCMs and ensuring the production of high quality TCMs by regulating rhizosphere microbial communities.

Scutellaria baicalensis(S. baicalensis) and Scutellaria barbata(S. barbata) are common medicinal plants of the Lamiaceae family. Both produce specific flavonoid compounds, including baicalein, scutellarein, norwogonin, and wogonin, as well as their glycosides, which exhibit antioxidant and antitumor activities. Here, we report chromosome-level genome assemblies of S. baicalensisand S. barbatawith quantitative chromosomal variation (2n= 18 and 2n= 26, respectively). The divergence of S. baicalensisand S. barbataoccurred far earlier than previously reported, and a whole-genome duplication(WGD) event was identified. The insertion of long terminal repeat elements after speciation might be responsible for the observed chromosomal expansion and rearrangement. Comparative genome analysis of the congeneric species revealed the species-specific evolutionof chrysin and apigenin biosynthetic genes, such as the S. baicalensis-specific tandem duplicationof genes encoding phenylalanine ammonia lyase and chalcone synthase, and the S. barbata-specific duplication of genes encoding 4-CoA ligase. In addition, the paralogous duplication, colinearity, and expression diversity of CYP82Dsubfamily members revealed the functional divergence of genes encoding flavone hydroxylase between S. baicalensisand S. barbata. Analyzing these Scutellariagenomes reveals the common and species-specific evolution of flavone biosynthetic genes. Thus, these findings would facilitate the development of molecular breeding and studies of biosynthesis and regulation of bioactive compounds.

Scutellaria baicalensis(S. baicalensis) and Scutellaria barbata(S. barbata) are common medicinal plants of the Lamiaceae family. Both produce specific flavonoid compounds, including baicalein, scutellarein, norwogonin, and wogonin, as well as their glycosides, which exhibit antioxidant and antitumor activities. Here, we report chromosome-level genome assemblies of S. baicalensisand S. barbatawith quantitative chromosomal variation (2n = 18 and 2n = 26, respectively). The divergence of S. baicalensisand S. barbataoccurred far earlier than previously reported, and a whole-genome duplication(WGD) event was identified. The insertion of long terminal repeat elements after speciation might be responsible for the observed chromosomal expansion and rearrangement. Comparative genome analysis of the congeneric species revealed the species-specific evolutionof chrysin and apigenin biosynthetic genes, such as the S. baicalensis-specific tandem duplicationof genes encoding phenylalanine ammonia lyase and chalcone synthase, and the S. barbata-specific duplication of genes encoding 4-CoA ligase. In addition, the paralogous duplication, colinearity, and expression diversity of CYP82Dsubfamily members revealed the functional divergence of genes encoding flavone hydroxylase between S. baicalensisand S. barbata. Analyzing these Scutellariagenomes reveals the common and species-specific evolution of flavone biosynthetic genes. Thus, these findings would facilitate the development of molecular breeding and studies of biosynthesis and regulation of bioactive compounds.

To synthesize graphene economically and efficiently, as well as to improve the interface bonding between graphene and metal and to recede the aggregation issue of graphene, in this work, an easy and scalable bottom-up strategy for the mass production of metal nanoparticles modified graphene nanoplates (GNPs) was proposed. Cu nanoparticles modified GNPs (Cu-GNPs) and Ni nanoparticles modified GNPs (Ni-GNPs) were fabricated through this method, and then compounded with Al via ball milling technique. The as-obtained Ni-GNPs/Al composite showed simultaneously improved strength and toughness compared with unreinforced Al, while the Cu-GNPs/Al composite presented a greater strengthening effect. The microstructure and interface of the two composites were carefully characterized and investigated to reveal the difference. First principle study was also adopted to explore the binding energy of different interface structures. This study could provide new insights into the fabrication of GNPs and the control of interface in GNPs/Al composites. [ABSTRACT FROM AUTHOR]

Developing high-performance Li-S batteries with high sulfur loading is highly desirable for practical application and remains a major challenge. To achieve this goal, the following requirements for designing carbon/metal compound composites need to be met: (i) the carbon materials need to exhibit suitable specific surface area, void structure, and electrical conductivity; (ii) the weight content of the metal compounds should be low; and (iii) the metal compounds need to show a strong adsorption and efficient electrocatalytic function for LiPSs. In this study, inspired by the body structure of an octopus, a new carbon/NiS2hierarchical composite is reported, in which the apical NiS2nanoparticles (0D) on a 1D carbon nanotubes (CNTs) are supported on a three-dimensional carbon (3DC) framework (3DC-CNTs-NiS2). The 3DC-CNTs-NiS2composite has a high specific surface area (271 m2g–1), good electrical conductivity, and low NiS2content (9.2 wt %), and the apical NiS2nanoparticles are capable of adsorption and electrocatalysis toward LiPSs, demonstrated by both electrochemical characterization and theoretical calculation. When used as a cathode host of the Li-S battery, it exhibits an ultra-stable cycling performance with a fade rate of 0.043% per cycle over 1000 cycles; even with a high S loading (6.5 mg cm–2with 90 wt % of S), the soft package battery delivers a high area capacity of 5.0 mAh cm–2under the E/S ratio of 5 μLEmg–1s. This work provides a new approach to design and fabricate multi-functional S hosts with high S loading.

Ceramic phase reinforced aluminum matrix composites (CAMCs) are widely used in high-tech fields represented by aerospace industry due to their advantages of high specific strength, high specific modulus, high thermal stability, and light weight. Strong interface bonding is a prerequisite for high performance of multiphase materials. Herein, a novel CAMC in situ reinforced by MgAl2O4particles and MgAlB4nanorods was prepared by vacuum hot-pressing combined with hot-extrusion process. A high-resolution transmission electron microscope was used to characterize the orientation relationship and interface structure between the ceramic phases and the aluminum matrix. Two orientation relationships (OR1 and OR2) of MgAl2O4/Al and one (OR3) of MgAlB4/Al are determined: OR1-[011]p//[011]Al, (11̅1)p//(11̅1)Al; OR2-[211]p//[011]Al, (113̅)p//(022̅)Al; OR3-[101̅0]R//[001]Al, (0002)R//(2̅20)Al. The MgAl2O4in OR1 forms a coherent interface with the aluminum matrix at (111) surface, while they form a 4 × 5 near coincidence site lattice (CSL) interface structure for OR2. In OR3, the MgAlB4forms an approximate coherent interface with Al matrix at its (0002) surface and a 2 × 5 CSL interface structure at its (011̅0) surface. First-principles calculations suggest that MgAl2O4combines to aluminum at (111) plane through covalent bonds, which means high interfacial bonding strength. The hot-extrusion process makes the ceramic phase evenly distributed in the matrix. The mechanical properties of the composites are greatly improved compared with pure aluminum.

An efficient and concise synthesis of various trifluoromethyl‐substituted cyclopropanes from a variety of dienes and enynes in the presence of cheap inorganic base potassium phosphate has been reported. This methodology features high yields (up to 89%), wide substrate scope and excellent functional group tolerance (25 examples). An efficient and green methodwas explored for the synthesis of trifluoromethyl‐substituted cyclopropanes from dienes and enynes with CF3CHN2in toluene. This method was enabled using cheap inorganic base and had a good functional group tolerance with high efficiency.

The shuttle behavior of soluble lithium polysulfides (LiPSs) and sluggish electrochemical conversion from LiPSs to Li2S lead to poor cycling performance, which is the major problem hindering the practical applications of lithium-sulfur (Li-S) batteries. Herein, we developed a one-pot carbothermal reduction method to synthesize new CoO nanoparticles decorated Co9S8(Co9S8/CoO) heterostructures with well-defined interfaces, in which CoO shows strong adsorption function and Co9S8has significant electrocatalysis function. The Co9S8/CoO heterostructures with rationally structural design can not only improve the chemical capturing between CoO and LiPSs but also facilitate the electrocatalytic activity of Co9S8involving the reaction from soluable LiPSs to insoluble Li2S2and subsequent solid-solid reaction from Li2S2to Li2S. The synergistic adsorption-electrocatalysis function is verified by both theoretical calculations and electrochemical characterizations. The Li-S cell with the Co9S8/CoO-Graphene coated separator exhibits a coulombic efficiency of approximately 100% and delivers a specific capacity of 925 mA h g−1with a fade rate of 0.049% per cycle over 1000 cycles under a high S loading (2.5 mg cm−2). This work provides an emerging view on the design of heterostructures with synergistic adsorption and electrocatalysis function for application in Li-S batteries and catalysis fields.

Currently, seldom studies have paid close attention to the impact of the defects and oxygen-containing functional groups on the surface of the graphene for composite applications. In this work, two typical graphene materials, namely graphene nanosheets synthesized by an in situ catalytic reaction and reduced graphene oxide (RGO), were adopted to fabricate reinforced copper matrix composites by spark plasma sintering. A harmful transitional interfacial layer made up of Cu/CuOx/amorphous carbon/RGO, resulted from interfacial reaction between Cu and RGO, were observed in the RGO/Cu composite. In contrast, the in situ synthesized graphene with fewer defect and lower oxygen level can realize clean graphene–Cu interface with Cu–O–C bonding and thus lead to much improved interface bonding and superior yield strength and tensile ductility. These results imply that the in situ synthesized graphene is more favorable for achievement of robust interfacial bonding for enhancing the mechanical properties of the graphene-Cu composites.

Three-dimensional (3D) carbon networks (3DCNs) enjoy the merits of high surface area, effective mass-transfer ability, and mechanical stability. The physicochemical properties of such materials not only depend on their microstructures but also rely on the assembly forms. This work achieves different assembly forms of 3DCNs on the macroscale from powder, monolith, to clay and reveals the relations between intermolecular forces and these assembly forms. With the “weak” van der Waals forces, only 3DCN powders are obtained. The N-doping effect increases the part of “strong” van der Waals forces, which enables 3DCNs assembled as a monolith and supports 43 000 times its own weight. Furthermore, the introduction of aniline molecules and the corresponding hydrogen bond connections make carbon networks to transform into a clay with superior ductility and plasticity. Considering that 3DCNs can be engineered into functionalized materials by in situ incorporation of functional components such as Fe3O4, the composites with controllable forms are treated as promising candidate materials used in various fields.

As a promising bifunctional electrocatalyst for water splitting, NiFe-layered double hydroxide (NiFe LDH) demonstrates an excellent activity toward oxygen evolution reaction (OER) in alkaline solution. However, its hydrogen evolution reaction (HER) activity is challenged owing to the poor electronic conductivity and insufficient electrochemical active sites. Therefore, a three-dimensional self-supporting metal hydroxide/oxide electrode with abundant oxygen vacancies is prepared by electrodepositing CeOxnanoparticles on NiFe LDH nanosheets. According to the density functional theory calculations and experimental studies, the oxygen vacancies at the NiFe LDH/CeOxinterface can be introduced successfully because of the positive charges accumulation resulting from the local electron potential difference between NiFe LDH and CeOx. The oxygen vacancies accelerate the electron/ion migration rates, facilitate the charge transfer, and increase the electrochemical active sites, which give rise to an efficient activity toward HER in alkaline solution. Furthermore, NF@NiFe LDH/CeOxneeds a lower potential of 1.51 V to drive a current density of 10 mA cm–2in overall water splitting and demonstrates a superior performance compared with the benchmark Pt/C and RuO2, which is indicated to be a promising bifunctional electrode catalyst.

Integrating MoS2with various carbonaceous matrices, especially graphene, has been extensively explored for lithium-ion storage. However, mostly reported MoS2/graphene/MoS2nanostructures have been suffering from their low yield, costly and time-consuming prepared methods as well as their polysulfide shuttling problem owing to a certain degree of adverse reaction to the electrolyte. Herein, layer-by-layer nitrogen-doped graphene/MoS2/nitrogen-doped graphene (NDG/MoS2/NDG) stacking heterostructure has been prepared through a scalable and low-cost in-situthermal decomposition-reduction method. This new NDG/MoS2/NDG exhibits high crystallization degree MoS2, intimate interface contacts and fully NDG coating, which can effective host the electrochemical products of Mo and soluble lithium polysulfide and restrain the adverse reaction to the electrolyte. As a result, it shows a high initial CE (84.3%), excellent high-rate cycle performance (552 mAh g−1at 1Ag−1after 600 cycles) and a high areal capacity (409 mAh g−1at 8.73mgcm−2) when evaluated as lithium-ion batteries (LIBs) anode. Moreover, we have systematically studied the Li-storage mechanism, which confirms that the NDG coating layer shows significantly effect and advantage on solving polysulfide shuttling problem. We believe that this work can open up an avenue for the rational design of various anode materials, such as NDG coated metal oxides and sulfides for high performance LIBs and other energy related field.

A three-dimensional cross-linked porous silver network (PSN) is fabricated by silver mirror reaction using polymer foam as the template. The N-doped porous carbon nanofibers (N-PCNFs) are further prepared on PSN by chemical vapor deposition and treated by ammonia gas subsequently. The PSN substrate serving as the inner current collector will improve the electron transport efficiency significantly. The ammonia gas can not only introduce nitrogen doping into PCNFs but also increase the specific surface area of PCNFs at the same time. Because of its large surface area (801 m2/g), high electrical conductivity (211 S/cm), and robust structure, the as-constructed N-PCNFs/PSN demonstrates a specific capacitance of 222 F/g at the current density of 100 A/g with a superior rate capability of 90.8% of its initial capacitance ranging from 1 to 100 A/g while applied as the supercapacitor electrode. The symmetric supercapacitor device based on N-PCNFs/PSN displays an energy density of 8.5 W h/kg with power density of 250 W/kg and excellent cycling stability, which attains 103% capacitance retention after 10 000 charge–discharge cycles at a high current density of 20 A/g, which indicates that N-PCNFs/PSN is a promising candidate for supercapacitor electrode materials.