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Emerging high entropy compounds (HECs) have attracted huge attention in electrochemical energy‐related applications. The features of ultrafine size and carbon incorporation show great potential to boost the ion‐storage kinetics of HECs. However, they are rarely reported because high‐temperature calcination tends to result in larger crystallites, phase separation, and carbon reduction. Herein, using the NaCl self‐assembly template method, by introducing a high‐pressure field in the calcination process, the atom diffusion and phase separation are inhibited for the general formation of HECs, and the HEC aggregation is inhibited for obtaining ultrafine size. The general preparation of ultrafine‐sized (<10 nm) HECs (nitrides, oxides, sulfides, and phosphates) anchored on porous carbon composites is realized. They are demonstrated by combining advanced characterization technologies with theoretical computations. Ultrafine‐sized high entropy sulfides‐MnFeCoCuSnMo/porous carbon (HES‐MnFeCoCuSnMo/PC) as representative anodes exhibit excellent sodium‐ion storage kinetics and capacities (a high rating capacity of 278 mAh g−1 at 10 A g−1 for full cell and a high cycling capacity of 281 mAh g−1 at 20 A g−1 after 6000 cycles for half cell) due to the combining advantages of high entropy effect, ultrafine size, and PC incorporation. Our work provides a new opportunity for designing and fabricating ultrafine‐sized HECs. [ABSTRACT FROM AUTHOR]

Powdery hexagonal boron nitride (h‐BN), as an important material for electrochemical energy storage, has been typically synthesized in bulk and one/two‐dimensional (1/2D) nanostructured morphologies. However, until now, no method has been developed to synthesize powdery three‐dimensional (3D) h‐BN. This work introduces a novel NaCl‐glucose‐assisted strategy to synthesize micron‐sized 3D h‐BN with a honeycomb‐like structure and its proposed formation mechanism. We propose that NaCl acts as the template of 3D structure and promotes the nitridation reaction by adsorbing NH3. Glucose facilitates the homogeneous coating of boric acid onto the NaCl surface via functionalizing the NaCl surface. During the nitridation reaction, boron oxides (BO4 and BO3) form from a dehydration reaction of boric acid, which is then reduced to O2‐B‐N and O‐B‐N2 intermediates before finally being reduced to BN3 by NH3. When incorporated into polyethylene oxide‐based electrolytes for Li metal batteries, 5 wt % of 3D h‐BN significantly enhances ionic conductivity and mechanical strength. Consequently, this composite electrolyte demonstrates superior electrochemical stability. It delivers 300 h of stable cycles in the Li//Li cell at 0.1 mA cm−2 and retains 89 % of discharge capacity (138.9 mAh g−1) after 100 cycles at 1 C in the LFP//Li full cell. [ABSTRACT FROM AUTHOR]

The water‐soluble salt‐template technique holds great promise for fabricating 3D porous materials. However, an equipment‐free and pore‐size controllable synthetic approach employing salt‐template precursors at room temperature has remained unexplored. Herein, we introduce a green room‐temperature antisolvent precipitation strategy for creating salt‐template self‐assembly precursors to universally produce 3D porous materials with controllable pore size. Through a combination of theoretical simulations and advanced characterization techniques, we unveil the antisolvent precipitation mechanism and provide guidelines for selecting raw materials and controlling the size of precipitated salt. Following the calcination and washing steps, we achieve large‐scale and universal production of 3D porous materials and the recycling of the salt templates and antisolvents. The optimized nitrogen‐doped 3D porous carbon (N‐3DPC) materials demonstrate distinctive structural benefits, facilitating a high capacity for potassium‐ion storage along with exceptional reversibility. This is further supported by in situ electrochemical impedance spectra, in situ Raman spectroscopy, and theoretical calculations. The anode shows a high rate capacity of 181 mAh g−1 at 4 A g−1 in the full cell. This study addresses the knowledge gap concerning the room‐temperature synthesis of salt‐template self‐assembly precursors for the large‐scale production of porous materials, thereby expanding their potential applications for electrochemical energy conversion and storage. [ABSTRACT FROM AUTHOR]

Tandem catalysis presents a promising strategy to improve the selectivity toward multicarbon products in the electrocatalytic carbon dioxide reduction reaction (CO2RR). For CO2RR, CO is a critical intermediate for producing multicarbon products. However, the management of CO localization and CO diffusion remains underexplored despite its critical role. Herein, a 3D tandem catalyst electrode with silver nanoparticles (Ag NPs) is designed to generate CO as an intermediate product within a copper (Cu) nanoneedle array. Via this nanostructured design, CO2 forms C2+ products with a high Faradaic efficiency (FEC2+) of 64% in an H‐cell and 70% in a flow cell with a current density of 350 mA cm−2. These figures‐of‐merit are currently among the top literature reports. More importantly, in situ Raman spectroscopy and finite‐element method calculations are employed to elucidate the origins of enhanced selectivity. These approaches reveal the crucial role of prolonging the CO diffusion path length for improving CO utilization during CO2 conversion with tandem catalyst systems. The favorable CO2RR FEC2+ in two distinct environments (H‐cell and flow cell) further corroborates that this effect is not limited to a particular reactor environment. Overall, this study provides new insights for designing tandem catalysts for improved CO2RR selectivity to C2+ products. [ABSTRACT FROM AUTHOR]

Sea buckthorn leaf tea, an emerging potential functional beverage product, has not yet had appropriate product standards and corresponding quality evaluation methods, and its poor taste directly affects the acceptance of the population, thus limiting its market consumption potential. In this study, two major packaging forms of sea buckthorn leaf tea available in the Chinese market were selected. The contents of total phenolics, total flavonoids, and 10 phenolic compounds, as well as the in vitro antioxidant capacity and sensory characteristics of sea buckthorn leaf tea were analyzed. Results showed that the quality of sea buckthorn leaf tea in the Chinese market varied widely. The total phenolic content, total flavonoid content, antioxidant activity, and consumer acceptance of bagged sea buckthorn leaf tea were higher than those of bulk sea buckthorn leaf tea. Multifactorial statistical analysis showed that the taste astringency of sea buckthorn leaf tea was closely related to ellagic acid and isorhamnetin‐3‐O‐neohesperidin. Furthermore, isorhamnetin‐3‐O‐neohesperidin had a greater effect on the antioxidant activity of sea buckthorn leaf tea. Therefore, ellagic acid and isorhamnetin‐3‐O‐neohesperidin can be used as potential quality markers for sea buckthorn leaf tea. This work provides a reference for taste improvement and quality control of sea buckthorn leaf tea. [ABSTRACT FROM AUTHOR]

Resource‐rich FeS2 is a promising anode for potassium‐ion batteries (PIBs). However, polysulfides emerge due to FeS2 conversion during discharging, which dissolve into the ether‐based electrolyte and cause the continuous capacity degradation in PIBs. To address the polysulfides dissolution in PIBs, a graphene–shell‐encapsulated FeS2 is fabricated and embedded in N/S codoped 3D hollow carbon spheres. As a protective pocket, the graphene–shell can effectively accommodate polysulfides inside the core–shell, inhibiting the polysulfides shuttle effect to enhance cycle stability of electrode. The density functional theory (DFT) calculations demonstrate that graphene–shells have a strong adsorption capacity for polysulfides, and the interfacial interaction between KFeS2 and graphene–shell can boost the K ion mobility. As a result, the composite exhibits superior‐rate properties (524 and 224 mA h g−1 at 0.1 and 8 A g−1, respectively) and long‐term cycle stability. This work demonstrates the promotion and protective effect of the graphene–shell for the FeS2 to storage K from both experimental and computational perspectives. These research outputs can provide guidance for designing other metal‐based sulfide electrodes for PIBs. [ABSTRACT FROM AUTHOR]

SUMMARY: Distant species producing the same secondary metabolites is an interesting and common phenomenon in nature. A classic example of this is scutellarein whose derivatives have been used clinically for more than 30 years. Scutellarein occurs in significant amounts in species of two different orders, Scutellaria baicalensis and Erigeron breviscapus, which diverged more than 100 million years ago. Here, according to the genome‐wide selection and functional identification of 39 CYP450 genes from various angiosperms, we confirmed that only seven Scutellaria‐specific CYP82D genes and one Erigeron CYP706X gene could perform the catalytic activity of flavone 6‐hydroxylase (F6H), suggesting that the convergent evolution of scutellarein production in these two distant species was caused by two independently evolved CYP450 families. We also identified seven Scutellaria‐specific CYP82D genes encoding flavone 8‐hydroxylase (F8H). The evolutionary patterns of CYP82 and CYP706 families via kingdom‐wide comparative genomics highlighted the evolutionary diversity of CYP82D and the specificity of CYP706X in angiosperms. Multi‐collinearity and phylogenetic analysis of CYP82D in Scutellaria confirmed that the function of F6H evolved from F8H. Furthermore, the SbaiCYP82D1A319D, EbreCYP706XR130A, EbreCYP706XF312D and EbreCYP706XA318D mutants can significantly decrease the catalytic activity of F6H, revealing the contribution of crucial F6H amino acids to the scutellarein biosynthesis of distant species. This study provides important insights into the multi‐origin evolution of the same secondary metabolite biosynthesis in the plant kingdom. Significance Statement: Here, we determined that the scutellarein accumulation in distant species from Lamiaceae and Asteraceae arose from the convergent evolution of Scutellaria‐specific CYP82D and Asteraceae‐specific CYP706X. The independent evolutionary pattern of CYP82 and CYP706 and the findings of crucial residues will provide novel insights into the convergent evolution of secondary metabolite biosynthesis in the plant kingdom. [ABSTRACT FROM AUTHOR]

Introduction: Chromones are the major constituents of agarwood and are considered to be directly related to its quality. Agarotetrol, a chromone derivative, is a Chinese Pharmacopoeia content detection index. However, comprehensive high‐performance liquid chromatography (HPLC), quantitative analysis of multiple components by a single marker (QAMS), and ultra‐performance liquid chromatography mass spectrometry (UPLC‐MS) analyses of this pharmacopeial plant material have never been performed. Moreover, reports regarding the separation and detection of multiple active 2‐(2‐phenylethyl)chromone analogues from this plant material are surprisingly scarce. Objective: To establish a simple, reliable, and effective HPLC method utilising both diode array and MS detection for the simultaneous determination of multiple active chromone analogues in agarwood. Methods: Four 2‐(2‐phenylethyl)chromones were isolated from methanol extracts of agarwood. After optimising the extraction, separation, and analytical conditions, validation of the developed analytical method indicated good linearity, satisfactory precision, and good recovery. On this basis, a method for the quantitative analysis of multiple components by a single marker was established. The four 2‐(2‐phenylethyl)chromones were identified by nuclear magnetic resonance spectroscopic analysis and UPLC coupled to electrospray ionisation quadrupole‐time‐of‐flight MS. Conclusions: The behaviour of the chromones characterised by MS fragmentation indicated a loss of molecular CO and the formation of m/z 121 compounds by the cleavage of CH2‐CH2 bonds between the chromone and phenyl moieties. Three detection methods were successfully used in this study for agarwood detection, and this protocol may potentially be used as a tool for the quality control of agarwood. Chromones are the major constituents of agarwood and are considered to be directly related to its quality. 2‐(2‐phenylethyl)chromones were isolated from methanol extracts of agarwood. To establish a simple, reliable, and effective HPLC method of multiple active chromone analogues in agarwood. The four 2‐(2‐phenylethyl)chromones were identified by nuclear magnetic resonance spectroscopic analysis and UPLC coupled to electrospray ionisation quadrupole‐time‐of‐flight MS. [ABSTRACT FROM AUTHOR]

Summary: Lonicera japonica is a widespread member of the Caprifoliaceae (honeysuckle) family utilized in traditional medical practices. This twining vine honeysuckle also is a much‐sought ornamental, in part due to its dynamic flower coloration, which changes from white to gold during development.The molecular mechanism underlying dynamic flower coloration in L. japonica was elucidated by integrating whole genome sequencing, transcriptomic analysis and biochemical assays.Here, we report a chromosome‐level genome assembly of L. japonica, comprising nine pseudochromosomes with a total size of 843.2 Mb. We also provide evidence for a whole‐genome duplication event in the lineage leading to L. japonica, which occurred after its divergence from Dipsacales and Asterales. Moreover, gene expression analysis not only revealed correlated expression of the relevant biosynthetic genes with carotenoid accumulation, but also suggested a role for carotenoid degradation in L. japonica's dynamic flower coloration. The variation of flower color is consistent with not only the observed carotenoid accumulation pattern, but also with the release of volatile apocarotenoids that presumably serve as pollinator attractants.Beyond novel insights into the evolution and dynamics of flower coloration, the high‐quality L. japonica genome sequence also provides a foundation for molecular breeding to improve desired characteristics. [ABSTRACT FROM AUTHOR]

The compression‐compression fatigue performance of carbon nanotube (CNT) reinforced aluminium matrix composite foams (AMCFs) were investigated. The ε‐N curves of AMCFs are composed of three stages (the elastic, strain hardening, and rapid accumulation stages), while the fatigue strain of AMCFs accumulates very rapidly in stage III compared with Al foams. The fatigue strength of AMCFs with CNT contents of 2.0, 2.5, and 3.0 wt% increases by 6%, 44%, and 102% than Al foams, respectively. Different from Al foams' deformation of layer‐by‐layer, the main failure modes of AMCFs are the brittle fracture and collapse of pores within significant shear deformation bands under fatigue loading. The uniform distribution of CNTs and good interfacial bonding of CNTs and Al matrix is the important factor for the improvement of fatigue properties of AMCFs. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) reinforced Al composite foams with different CNT contents are fabricated through an improved powder metallurgy approach by combining in-situ chemical vapor deposition (CVD), short time ball-milling, and space-holder method. The CNTs are uniformly dispersed on the surface of Al particles by in-situ CVD process, followed by a short time ball-milling process enabling an excellent interfacial bonding between CNTs and the Al matrix. The pore size and microstructures of the composite foams can be well tailored by the carbamide particle templates. The yield strength and energy absorption capacity of composite foams reach 18.1 MPa and 15.8 MJ m−3 with 3.0 wt% CNT addition, which are ≈1.3 and ≈3.6 times higher than those of pure Al foam, respectively. The energy absorption efficiency of the CNT/Al composite foams achieves a maximum of ≈0.86, when the CNT content is up to 3.0 wt%. Additionally, compressive and energy absorption properties of the CNT/Al composite foams increase with the increment of relative density. The failure mode of the Al foam changes from plastic mode to brittle mode combined with ductile mode, as a result of CNT addition. [ABSTRACT FROM AUTHOR]

A general ultrathin-nanosheet-induced strategy for producing a 3D mesoporous network of Co3O4 is reported. The fabrication process introduces a 3D N-doped carbon network to adsorb metal cobalt ions via dipping process. Then, this carbon matrix serves as the sacrificed template, whose N-doping effect and ultrathin nanosheet features play critical roles for controlling the formation of Co3O4 networks. The obtained material exhibits a 3D interconnected architecture with large specific surface area and abundant mesopores, which is constructed by nanoparticles. Merited by the optimized structure in three length scales of nanoparticles-mesopores-networks, this Co3O4 nanostructure possesses superior performance as a LIB anode: high capacity (1033 mAh g−1 at 0.1 A g−1) and long-life stability (700 cycles at 5 A g−1). Moreover, this strategy is verified to be effective for producing other transition metal oxides, including Fe2O3, ZnO, Mn3O4, NiCo2O4, and CoFe2O4. [ABSTRACT FROM AUTHOR]

High energy density and power density within a limited volume of flexible solid-state supercapacitors are highly desirable for practical applications. Here, free-standing high-quality 3D nanoporous duct-like graphene (3D-DG) films are fabricated with high flexibility and robustness as the backbones to deposit flower-like MnO2 nanosheets (3D-DG@MnO2). The 3D-DG is the ideal support for the deposition of large amount of active materials because of its large surface area, appropriate pore structure, and negligible volume compared with other kinds of carbon backbones. Moreover, the 3D-DG preserve the distinctive 2D coherent electronic properties of graphene, in which charge carriers move rapidly with a small resistance through the high-quality and continuous chemical vapor deposition-grown graphene building blocks, which results in a high rate performance. Marvelously, ultrathin (≈50 μm) flexible solid-state asymmetric supercapacitors (ASCs) using 3D-DG@MnO2 as the positive electrode and 3D hierarchical nanoporous graphene films as the negative electrode display ultrahigh volumetric energy density (28.2 mW h cm−3) and power density (55.7 W cm−3) at 2.0 V. Furthermore, as-prepared ASCs show high cycle stability clearly demonstrating their broad applications as power supplies in wearable electronic devices. [ABSTRACT FROM AUTHOR]

The interface between metal matrix and reinforcement significantly affects mechanical properties of metal matrix composites (MMCs), but the interplay mechanism among the interface microstructure, the interface binding, and the mechanical properties is still unclear. Herein, the interface microstructure and interface binding of β‐SiC (111)/α‐Ti (0001) composite are regulated through the introduction of Sc, Y, Mg, Al, Si, Ni, Cu, and Mn dopants. Adhesive work and elastic properties of different doped interfaces are studied by first‐principles calculations. It is found that the elastic modulus does not directly relate to the adhesive work. The analysis of the electronic structure reveals that dopants change interface bonding states, which results in the localization of the interface electron distribution and enhances the elastic modulus. However, the lattice distortion induced by the dopants causes a significant decrease in the elastic modulus. Combined with the analysis of the adhesive work and interface electronic and atomic structure, the microscopic mechanism of the dopant‐induced electronic localization to regulate elastic properties of SiC/Ti composite is established. The new mechanism is helpful to understand the relationship among the interface microstructure, the interface binding, and the elastic properties, and to design MMCs with improved elastic properties. [ABSTRACT FROM AUTHOR]

In article number 1600755, Enzuo Liu, Naiqin Zhao, and co‐workers report ultrathin flexible solid‐state asymmetric supercapacitors using 3D nanoporous duct‐like graphene @ MnO2 films as the positive electrode and 3D hierarchical nanoporous graphene films as the negative electrode that display ultrahigh volumetric energy and power densities, demonstrating broad applications as power supplies in wearable electronic devices. [ABSTRACT FROM AUTHOR]

Review: 85 refs. [ABSTRACT FROM AUTHOR]