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The remarkable progress in the fields of aerospace, transportation, electronic packaging, and other industries has sparked a growing need for Al matrix composites (AMCs) with extraordinary mechanical properties. As ideal reinforcements for fabricating lightweight AMCs, oxide ceramics have garnered extensive attention due to their impressive attributes such as exceptional strength, high melting point, commendable chemical stability and resistance to oxidation. Especially, the AMCs reinforced with in situ oxide ceramics have shown more promising prospects for enhancing the compatibility of reinforcement-matrix interface and manipulating reinforcement dispersion compared to the counterparts with ex situ reinforcements, as they usually involve the formation of reinforcements through in situ chemical reactions between elements or compounds. This review focuses on recent advancements in preparation strategies, exploring the in situ reaction mechanisms and microstructural characteristics, as well as unraveling the remarkable mechanical properties of in situ oxide ceramic-reinforced AMCs. The crucial role of in situ reactions in governing reinforcement characteristics such as distribution, size, dimension, and the reinforcement-matrix interfacial structure is particularly underscored. The review is expected to facilitate a comprehensive understanding of the interplay between the various facets of the subject, which hold significant implications for guiding the development of high-performance AMCs. [ABSTRACT FROM AUTHOR]

The damping properties of Al matrix composite foams reinforced by in-situ grown carbon nanotubes (CNTs) have been investigated. The results show that the damping capacity of the CNT/Al composite foams is visibly enhanced with the CNT addition. The loss factors of the composite foams are found not only increase with the increment of CNT content but also increase with the porosity raising. For the 3.0 wt%-CNT/Al composite foams, the loss factor keeps the level of ∼0.26 at 25–200 °C and further increases to 0.36 when the temperature is elevated to 390 °C, which is ∼2.71 and 1.77 times higher than that of the pure Al foam, respectively. The damping improvement of CNT/Al composite foams is mainly due to the high inherent damping of CNTs and the formation of large numbers of well-bonded CNT-Al interfaces. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Paeonia suffruticosa Andrews (PSE) is a well-known Chinese medicine that has been widely used as an anti-tumor, anti-oxidative and anti-inflammatory agent. cis - and trans -gnetin H are two resveratrol oligomers isolated from the seeds of PSE. Although resveratrol is widely considered to be one of the most valuable natural chemopreventive agents and there are numerous studies on the antitumor activities of resveratrol, little is known about the antitumor properties of cis - and trans -gnetin H. Materials and methods The inhibitory effects of cis - and trans -gnetin H in different human cancer cell lines were assessed using fluorescent viability tests. Cytotoxicity in human lung and breast cancer cells was detected via nuclear condensation, cell permeability, and changes in the mitochondrial membrane potential (∆ψm). Apoptosis in human lung and breast cancer cells was assessed by flow cytometry, a luminescence assay and high-content screening analysis. Finally, a xenograft mice model was used to examine the efficacy of cis -gnetin H on lung tumors. Results cis - and trans -gnetin H have superior activity in inhibiting the proliferation of four human cancer cell lines, A549 (lung), BT20 (breast), MCF-7 (breast) and U2OS (osteosarcoma), and promote cell apoptosis, while having a minimal effect on two normal human epithelial cell lines, HPL1A (lung) and HMEC (breast) used as controls. cis - and trans -gnetin H promote apoptosis by releasing mitochondria cytochrome c , activating caspase 3/7 and inhibiting NF-κB activation. Flow cytometry analysis shows that cis - or trans -gnetin H arrested the cell cycle of cancer cells at the G0–G1 phase. Moreover, cis -gnetin H suppressed the growth of xenograft lung tumors in mice. Conclusion Collectively, our findings demonstrate the promise of the natural compounds cis - and trans -gnetin H as candidates for cancer chemotherapy agents. [ABSTRACT FROM AUTHOR]

The section Moutan of the genus Paeonia consists of eight species that are confined to a small area in China. A wide range of metabolites, including monoterpenoid glucosides, flavonoids, tannins, stilbenes, triterpenoids, steroids, paeonols, and phenols, have been found in the species belonging to section Moutan . However, although previous studies have analyzed the metabolites found in these species, the metabolic similarities that can be used for the chemotaxonomic distinction of section Moutan species are not yet clear. In this study, HPLC–DAD-based metabolic fingerprinting was applied to the classification of eight species: Paeonia suffruticosa , Paeonia qiui , Paeonia ostii , Paeonia rockii , Paeonia jishanensis , Paeonia decomposita , Paeonia delavayi , and Paeonia ludlowii . In total, of the 47 peaks that exhibited an occurrence frequency of 75% in all 23 tree peony samples, 43 of these metabolites were identified according to their retention times and UV absorption spectra, together with combined HPLC–QTOF-MS. These data were compared with reference standard compounds. The 43 isolated compounds included 17 monoterpenoid glucosides, 11 galloyl glucoses, 5 flavonoids, 6 paeonols and 4 phenols. Principal component analysis (PCA), and hierarchical cluster analysis (HCA), showed a clear separation between the species based on metabolomics similarities and four groups were identified. The results exhibited good agreement with the classical classification based on the morphological characteristics and geographical distributions of the subsections Vaginatae F.C. Stern and Delavayanae F.C. Stern with the exception of P. decomposita , which was found to be a transition species between these two subsections. According to their metabolic fingerprinting characteristics, P. ostii and P. suffruticosa can be considered one species, and this result is consistent with the viewpoint of medicinal plant scientists but different from that of classical morphological processing. Significantly large variations were obtained in the metabolic profiles of P. delavayi , whereas no significant difference was found between P. delavayi and P. ludlowii . This indicates that these two species have a close genetic relationship. In conclusion, the combination of HPLC–DAD and multivariate analyses has great potential for guiding future chemotaxonomic studies to examine the potential pharmaceutical value of the effective constituents of tree peony species and appears to be able to clarify the confusion and skepticism associated with the reported morphology- and molecular phylogenetics-based taxonomy of tree peonies. [ABSTRACT FROM AUTHOR]

Paeonia is famous as ornamental, medicinal plant, and edible oil crop in China. The seeds of peonies are rich in unsaturated fatty acids, monoterpene glycosides, sterols and stilbenes which have antioxidant and anti-inflammatory effects, etc. In this study, the composition and content of stilbenes in the seed coat extracts (SCE) from 50 populations of 18 species and two subspecies of Paeonia were determined by high performance liquid chromatography - diode array detection (HPLC-DAD). The results showed that the composition and content of stilbenes, especially suffruticosol B and gnetin H, differed significantly between Paeonia species, while there were small differences between populations of the same species. All the samples were clustered into two groups according to the stilbenes in SCE. The difference between the two groups was mainly reflected in the content of suffruticosol B and gnetin H. Furthermore, all samples showed high antioxidant activity, which was significantly positively correlated with the total polyphenol content. The SCE of P. anomala and P. lactiflora at different concentrations could effectively inhibit the production of matrix metalloproteinase − 1 (MMP-1) in keratinocytes, and then achieve the effect of inhibiting cell aging. This study provided a valuable reference for the value-added utilization of Paeonia seed coat. ● Paeonia seed coat is rich in stilbenes, most of them are resveratrol trimer. ● Suffruticosol B and gnetin H are the two stilbenes with the highest content in Paeonia seed coat. ● Paeonia seed coat extract can effectively inhibit the production of matrix metalloproteinase −1 in skin keratinocytes. ● Paeonia seed coat can be used as a new resource to develop anti- photoaging products. [ABSTRACT FROM AUTHOR]

Highlights: [•] A mass of amorphous carbon nanotubes have been synthesized. [•] The Fe76Si9B10P5 particles were employed as both the catalyst and support. [•] C2H2 and Ar were employed as carbon precursor and carrier gas, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A rapid, sensitive, and accurate HPLC-DAD method was developed and validated for simultaneous determination of one phenolic glycoside and seven monoterpene glycosides, including 1-O-β-d-(4-hydroxybenzoyl)glucose (1), pyridylpaeoniflorin (2), (8R)-piperitone-4-en-9-O-β-d-glucopyranoside (3), oxypaeoniflorin (4), 6′-O-β-glucopyranosylalbiflorin (5), albiflorin (6), β-gentiobiosylpaeoniflorin (7), and paeoniflorin (8), in 44 batches of peony seeds from nine Paeonia species collected from different areas. Using the optimised method, separations were conducted with a YMC-pack ODS-A column with water/formic acid and methanol as the mobile phase. All eight analytes demonstrated good linearity (r 2 >0.9993). The recoveries, measured at three concentration levels, varied from 98.20% to 103.81%. Six compounds including 1 and 4–8 occur ubiquitously in all the seeds of nine Paeonia species, and compounds 2 and 3 showed undetectable levels or very low content in several samples. The seed samples were classified into several groups, which coincide with the taxonomy of Paeonia at the section level. Peony seed might be a useful resource in developing new herbal or food products. [Copyright &y& Elsevier]

Background: Radix Paeoniae Alba, Radix Paeoniae Rubra, and Cortex Moutan are important Chinese herbs. Their bioactivities and efficacies are similar. However, they have different superior benefits clinically; so, a comprehensive investigation of the chemical difference is necessary and is of great importance for more reasonable quality assessment and proper clinical application of these three herbal medicines. Objective: To establish a high-performance liquid chromatography (HPLC) fingerprint method for the quality control of Radix Paeonia Alba, Radix Paeonia Rubra, and Cortex Moutan, and to compare their main constituents. Materials and Methods: The separations of Radix Paeoniae Alba, Radix Paeoniae Rubra, and Cortex Moutan was carried out, respectively, through a gradient elution using a monolithic column and a mobile phase consisting of water (containing 0.1% formic acid) and acetonitrile (containing 0.1% formic acid) at a flow rate of 5.0 ml/min. The detection wavelength was set at 230 nm. The data calculation was performed with CHROMAP v1.51 and Statistical Package for the Social Sciences (SPSS) 18.0 software for principal component analysis. Results: A rapid separation method based on high-performance liquid chromatography with diode-array detection (HPLC-DAD) with monolithic columns and a fingerprint analysis method was established. Fifteen Radix Paeonia Alba, 45 Radix Paeonia Rubra, and 21 Cortex Moutan samples were analyzed and 11 chromatographic peaks were identified. Differences of chromatographic peaks among these three herbal medicines in chemical compositions were revealed. Conclusion: The separation and analysis method are fast and simple, which can be used for chemical fingerprint comparison of Radix Paeonia Alba, Radix Paeonia Rubra, and Cortex Moutan. The results for the evaluation of the three medicines could provide experimental evidence for chemical affinity. [ABSTRACT FROM AUTHOR]

Abstract: Three types of carbon nanomaterials, including bamboo-shaped carbon nanotubes with Ni encapsulated and hollow and Ni catalytic particles filled carbon nanocages, have been prepared by methane catalytic decomposition at a relatively low temperature. Transmission electron microscopy observations showed that fascinating fullerene-like Ni–C (graphitic) core–shell nanostructures predominated. Detailed examination of high-resolution transmission electron microscopy showed that the walls of bamboo-shaped carbon nanotubes with quasi-cone catalytic particles encapsulated consisted of oblique graphene planes with respect to the tube axis. The Ni particles encapsulated in the carbon nanocages were larger than that encapsulated in carbon nanotubes, but the diameters of the cores of hollow carbon nanocages were less than that of Ni particles encapsulated in carbon nanotubes, suggesting that the sizes of catalyst particles played an important role during carbon nanomaterial growth. The magnetic properties of the carbon nanomaterials were measured, which showed relatively large coercive force (H c =138.4Oe) and good ferromagnetism (M r/M s =0.325). [Copyright &y& Elsevier]

Abstract: Novel binary and triple carbon nanotubes (CNTs) with one common catalytic particle encapsulated have been synthesized using Ni/Cu/Al2O3 catalyst, which was produced by a sol–gel method. But when using Ni/Al2O3 as catalyst, a mass of common CNTs, that is, one CNT with one catalytic particle encapsulated, was obtained. The results showed that copper-element doping to the Ni/Al2O3 catalyst played a key role in the synthesis of CNTs, signifying a novel approach to modify the Ni/Al2O3 catalyst. Based on the transmission electron microscopy observations, a simple growth mechanism was developed to describe the growth of the binary or triple CNTs, which could be well explained by a diffusion segregation process. [Copyright &y& Elsevier]

Abstract: The initial stage growth of bamboo-shaped carbon nanotubes (CNTs) synthesized by catalytic decomposition of methane is investigated. A special experimental procedure has been developed to stop the process after short durations (0s to 3min). It has found that during the early stages (60s), carbon cluster-encapsulated nanoparticles are formed. With prolonging synthesis time (3min), some CNTs coexisted with carbon cluster-encapsulated nanoparticles are formed. HRTEM observations show that these CNTs display multi-walled and bamboo structure and the encapsulated catalytic particles are quasi-cone morphologies. At the same time, the catalytic particles only encapsulated with carbon clusters present quasi-sphere structures. For growth up to 60min, two kinds of bamboo mode structures are observed: conical, and cylindrical, which are developed by quasi-cone and quasi-sphere catalytic particles, respectively. Moreover, the early stage growth mode of the CNTs is predominantly of the base growth mode according to TEM observations. [Copyright &y& Elsevier]

Abstract: A series of treatment processes were employed to purify and then physically activate the multi-walled carbon nanotubes obtained using catalytic decomposition of methane. In order to characterize and compare the activation effect, the carbon fibers were also treated by the same activation processes. The results showed that the normal physical activation by CO2 or steam has not too much effect on the surface area of purified multi-walled carbon nanotubes, in particular, the carbon nanotubes were burned when using the poignant activation conditions. However, the surface area of carbon fibers availably etched in the same activation processes is much increased. In addition, the mechanisms of physical activation on multi-walled carbon nanotubes and carbon fibers have been investigated. [Copyright &y& Elsevier]

Abstract: The possibility of using aluminum powder as transition metal catalyst carrier for CVD growth of carbon nanotubes (CNTs) has been investigated. The fabrication process of Ni/Al catalyst involved the production of binary colloid (Ni(OH)2/Al) by deposition–precipitation method, followed by calcination in N2 and reduction in H2. The nickel particles obtained were with uniform diameters. After the catalytic synthesis at 600°C a mass of well-graphitized multi-walled CNTs with the diameters in the 10–20nm range have been obtained, as evidenced by HRTEM. The operated catalytic particle encapsulated in CNT was nickel according to EDX analysis. However, when using pure nickel without aluminum as the catalyst, no CNTs have formed due to the agglomeration of Ni particles. Thus we speculated that the aluminum powder was responsible for the formation and the even dispersion of the nano-scale transition metal particles. [Copyright &y& Elsevier]

Abstract: The purification effects of different methods including liquid oxidation by nitric acid and multi-step treatment on two raw CNT samples fabricated by CVD under different synthesis conditions were investigated. Opening effects of the purified CNTs were also explored. The results showed that the liquid oxidation by nitric acid has some effects on purification and opening of the CNTs, and that the effects vary with the CNT morphologies. When using multi-step treatment method, apparent effects of purification and opening on the CNTs are obtained. [Copyright &y& Elsevier]

Abstract: Carbon onions with diameters ranging from 5 to 50nm and carbon-coated nickel nanoparticles with diameters ranging from 10 to 60nm have been synthesized on a large scale over Ni/Al catalyst by chemical vapor deposition. The approximate ratio of Ni-filled to empty onions as observed by TEM is 1:3.5. In order to eliminate the nickel nanoparticle and obtain pure hollow carbon onions, HNO3 acid was used to dissolve the nickel from the carbon-coated nickel nanoparticles. The carbon onion particles thus obtained have hollow cores and are mainly composed of well-crystallized graphite, as characterized by high-resolution TEM and Raman spectroscopy. In addition, we proposed a simple purification mechanism for Ni-filled carbon onions based on TEM observations. [Copyright &y& Elsevier]

Abstract: A mass of carbon onions have previously been successfully synthesized via catalytic decomposition of methane using nitrogen as a carrier gas over a Ni/Al catalyst. In this study, X-ray photoelectron spectroscopy characterization of the carbon onions shows that the as-grown carbon onions contained nitrogen and that the nitrogen concentration in the carbon onions increased with an increase in reaction time. When hydrogen is used as a carrier gas, it is found that no carbon onions are obtained, indicating that the carrier gas plays an important role in the synthesis of carbon onions and that there is an intimate relationship between carbon onion growth and nitrogen incorporation. [Copyright &y& Elsevier]

Abstract: Ni/Al catalysts with different Ni concentrations have been used successfully for the synthesis of carbon nanotubes and onions from methane by chemical vapor deposition. The catalyst nanoparticles were produced by a deposition–precipitation method, and the carbon products by the catalytic decomposition of methane at 600°C. Carbon nanotubes (CNTs) were formed in the presence of a Ni/Al composite catalyst containing 20wt.% nickel. The CNTs were multi-walled, 10–20nm in diameter and up to 15μm long. Hollow carbon onions were produced in the presence of a Ni/Al composite catalyst containing 80wt.% nickel. The carbon onions were from 5 to 50nm in diameter and consisted of several concentric carbon layers surrounding a hollow core. The mechanisms for the formation of both the CNTs and carbon onions were discussed on the basis of the experimental results. [Copyright &y& Elsevier]

Abstract: The synthesis of carbon nanotubes (CNTs) by chemical vapor deposition (CVD) of methane on catalyst of Ni–Cu–Al powder was reported. The influence factors on the growth morphology of CNTs, such as reaction time and different carrier gases concerning hydrogen, nitrogen as well as no carrier gas were investigated using SEM and TEM. The results showed that the reaction time brought no significant influence to the diameter of CNTs, but the average length of the CNTs was obviously increased with prolonging the reaction time. Relatively pure CNTs could be obtained with hydrogen as the carrier gas but with poor product rate compared with the CNTs with no carrier gas. Proper amount of CNTs with pure characteristic could be obtained with nitrogen as the carrier gas. Finally, a growth mechanism of section-seal is proposed for analyzing the growth process of general CNTs. [Copyright &y& Elsevier]

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]

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]

Temperature changes caused by thermal effects greatly impact the performance of lithium-ion batteries. It is necessary to figure out the source of heat to assist battery thermal management, and to predict the battery temperature in order to warn the abnormal situation. Herein, this work demonstrate a series of data-driven approaches to analyze the battery thermal effects. From the perspective of time series data, we decompose the temperature change during the battery operation to distinguish the reversible heat and the irreversible heat. The strong correlation between reversible heat and charge/discharge current is verified. Meanwhile, it is found that the irreversible heat have a severe effect on the overall temperature in the later period of battery lifespan. Besides, the long short-term memory (LSTM) model is applied to predict the battery temperature changes. Relying on this machine learning method, we can accurately compute the temperature value of the battery at a certain time. Moreover, using the average temperature of each cycle as the training data, the temperature fluctuation of the battery can be efficiently predicted in a long period, which can serve as the battery temperature prognostic. Image 1 • Data-driven approaches are used to analyze the battery thermal effects. • The temperature of battery can be treated as time series data. • The contribution of reversible heat and irreversible heat are decoupled. • Long short-term memory method is used to predict the temperature change. [ABSTRACT FROM AUTHOR]

In the practical application of electromagnetic wave (EMW) absorbers, two important factors that simultaneously meet the lightweight characteristics and efficient absorption performance still face considerable challenges. In this work, the ultra-lightweight CoNi alloy nanoparticles uniformly distributed modified carbon nanofiber composites (CoNi@CNFs) was prepared by an ion-etching strategy. The carbon fibers create a three-dimensional conductive network that enhances the absorber's conduction loss capability. The polarization loss is enhanced by the defects in the carbon skeleton and the numerous heterogeneous interfaces formed between the carbon fibers and the surface of CoNi metal particles. The impedance matching property of CoNi@CNFs is optimized by the magnetic dielectric synergistic effect produced by the Ni2+ etching process. At a frequency of 17.58 GHz, the minimum reflection loss (RLmin) can reach − 52.34 dB, and the effective absorption bandwidth covers the complete Ku band at 7.0 GHz (11.0–18.0 GHz). In the range of − 60° to 60°, the radar cross-section values of the samples, calculated using CST simulation, are less than − 10 dBm2. This is critical for realizing the stealth capability of EMWs in high-frequency environments. This study provides an effective strategy for developing highly absorbent, lightweight EMW absorbers with practical potential applications. [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]

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 co-segregation of Cu and Mg solutes at grain boundaries (GBs) in Al alloys is widely observed in experiments, but this segregation pattern is much less understood. Herein, the Cu, Mg co-segregation behaviors and their effects on Al Σ5 (210) GB properties were systematically studied via first-principles calculations. The segregation order of Cu and Mg atoms was firstly determined wherein the segregation tendency of Cu is comparatively stronger than Mg. Calculations demonstrate that Cu and Mg atoms exhibit attractive interaction, which would promote synergistic co-segregation of both dopants at the GB. It is revealed that Cu, Mg co-segregation not only improves GB thermodynamic stability, but also enhances the GB fracture strength. Detailed analysis of charge density, bonding characteristics, etc., suggests that the newly formed Al–Cu bonds upon Cu segregation are the primary contribution to the increased GB cohesion. The further Mg doping at the Al GB with Cu segregation results in charge depletion and meanwhile decreases Al–Cu bonding length, the net results of which increase GB cohesion, suggesting a synergistically enhanced GB strength with Mg and Cu co-segregation. This work is supposed to provide fundamental insights into the effect of Cu, Mg co-segregation on the strength of Al GBs. [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]

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]

To support the global goal of carbon neutrality, numerous efforts have been devoted to the advancement of electrochemical energy conversion (EEC) and electrochemical energy storage (EES) technologies. For these technologies, transition metal dichalcogenide/carbon (TMDC/C) heterostructures have emerged as promising candidates for both electrode materials and electrocatalysts over the past decade, due to their complementary advantages. It is worth noting that interfacial properties play a crucial role in establishing the overall electrochemical characteristics of TMDC/C heterostructures. However, despite the significant scientific contribution in this area, a systematic understanding of TMDC/C heterostructures' interfacial engineering is currently lacking. This literature review aims to focus on three types of interfacial engineering, namely interfacial orientation engineering, interfacial stacking engineering, and interfacial doping engineering, of TMDC/C heterostructures for their potential applications in EES and EEC devices. To accomplish this goal, a combination of experimental and theoretical approaches was used to allow the analysis and summary of the fundamental electrochemical properties and preparation strategies of TMDC/C heterostructures. Moreover, this review highlights the design and utilization of the interfacial engineering of TMDC/C heterostructures for specific EES and EEC devices. Finally, the challenges and opportunities of using interfacial engineering of TMDC/C heterostructures in practical EES and EEC devices are outlined. We expect that this review will effectively guide readers in their understanding, design, and application of interfacial engineering of TMDC/C heterostructures. [ABSTRACT FROM AUTHOR]

Performance of a mechanical buffer can be significantly improved by strengthening the materials and optimizing its structure. Manufacturing of high-strength and light-weight foam-filled tubes (FFTs) has been proved to be an ingenious strategy. In this work, the in situ grown carbon nanotubes (CNTs) were used to reinforce aluminum (Al) foams. The FFTs were prepared by inserting CNT/Al composite foams (CFs) into 6061 Al alloy empty tubes (ETs). The crushing behavior and energy absorption property of the as-prepared CNT/Al FFTs (C-FFTs) were evaluated using uniaxial compressive tests. The results show that the adopted CFs can effectively interact with outside tubes in C-FFTs. The C-FFTs significantly improve the compressive performance and energy absorption property, but only slightly increase the structure weight compared to single ETs. The plateau stress and energy absorption capacity of C-FFTs are nearly 3.5 and 3.7 times higher than those of ETs, respectively. This phenomenon is ascribed to the stable support of CFs and the excellent load transfer ability of CNTs. [ABSTRACT FROM AUTHOR]

The controllable design of composition and structure makes incorporating reinforcements to be a promising way to fabricate aluminum (Al) composite foams. In this work, graphene nanosheets (GNSs) decorated with copper (Cu) nanoparticles reinforced Al composite foams are successfully synthesized via shift-speed ball-milling and space-holder method. The compressive properties and energy absorption capacity of composite foams increase first and then decrease with the increase of the GNSs@Cu content. Unexpectedly, the introduction of the GNSs@Cu has not changed the ductile failure mode of pure Al foams. The strengthening mechanisms of composite foams include load transfer strengthening and dispersion strengthening, and the toughening mechanism of composite foams is considered as crack bridging. The 0.75 wt% GNSs@Cu/Al composite foams possess the optimal yield stress (24.7 MPa), plateau stress (41.3 MPa) and energy absorption capacity (22.8 MJ/m3), which has an improvement of 104.7%, 113.7% and 115.1% in comparison with that of pure Al foams. Image 1 [ABSTRACT FROM AUTHOR]

[Display omitted] Developing highly efficient, low-cost, and stable bifunctional oxygen electrocatalysts is essential for the wide popularization of rechargeable Zn-air batteries. Combining zero-dimensional metal nanoparticles with two-dimensional metal oxide nanosheets is an appealing strategy to balance performance and cost. However, the precise construction of these composites remains a great challenge, and their interaction mechanisms lack thorough study. Herein, a cobalt-oxide-based bifunctional oxygen electrocatalyst comprising a rich Co-CoO heterointerface (CoO/Co@NG) was synthesized via a NaCl sealing-assisted pyrolysis strategy. The NaCl crystals played the role of a closed nanoreactor, which facilitated the formation of a CoO-Co heterojunction. Experimental results and theoretical calculations confirmed that the ingeniously constructed heterojunction expedited the oxygen reduction reaction and oxygen evolution reaction kinetics, which is superior to Pt/C. When serving as the air electrode in an assembled liquid-state Zn-air battery, the battery shows high power density (215 mW cm−2), specific capacity (710 mAh g zn −1), and outstanding durability (720 h at 10 mA cm−2). This work provides an innovative avenue to design high-performance heterojunction electrocatalysts for perdurable Zn-air batteries. [ABSTRACT FROM AUTHOR]

Highlights • A novel and efficient method to fabricate CNTs reinforced Al alloy matrix composite foams is put forward. • CNTs are homogeneously dispersed in the matrix. • The effects of CNTs on pore structure during foaming process is discussed. Abstract Uniformly dispersed carbon nanotubes (CNTs) reinforced aluminum (Al) alloy matrix composite foams were successfully fabricated by the combination of in-situ chemical vapor deposition and powder metallurgy using titanium hydride as a blowing agent. The effects of CNTs on the pore structure were systematically studied. The results showed that compared to the Al alloy foam, the introduction of CNTs could significantly improve the pore uniformity and reduce the pore size. As a result, the compressive property of composite foam had an obvious increase. The reasons for the enhanced pore structure mainly lie in that the CNTs increased nucleation sites for the decomposed hydrogen and the limited the movements of bubbles in the melt during foaming process. [ABSTRACT FROM AUTHOR]

Review: 85 refs. [ABSTRACT FROM AUTHOR]

Ultralight (<10 mg/cm3) cellular materials are desirable for thermal insulation; battery electrodes; catalyst supports; and acoustic, vibration, or shock energy damping. However, most of these ultralight materials, especially ultralight metal foams, are fabricated using either expensive materials or complicated procedures, which greatly limit their large-scale production and practical applications. Here we report a simple and versatile method to obtain ultralight monolithic metal foams. These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating. We have produced ultralight monolithic metal foams, such as silver, nickel, cobalt, and copper via this method. The resultant ultralight monolithic metal foams have remarkably low densities down to 7.4 mg/cm3 or 99.9% porosity. The metal foams have a long flat stress-train curve in compression tests and the densification strain εD of the Ni/Ag foam with a porosity of 99.8% can reach 82%. The plateau stress σpl was measured and found to be in agreement with the value predicted by the cellular solids theory. [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]

Ethnopharmacological relevance Reactive oxygen species (ROS) mediate vascular cell dysfunction and lead to atherosclerosis and other chronic cardiovascular diseases. The root of Pueraria lobata (Willd.) Ohwi, also known as kudzu or Gegen (Chinese name), is one of the most important herbs in traditional Chinese medicine and has been widely used in the treatment of cardiovascular diseases, diabetes, osteonecrosis and neurodegradation diseases. In this study, an ethanol extract from kudzu root was prepared and the in vitro protective effect of the kudzu root extract (KUD) on human umbilical vein endothelial cells (HUVECs) was investigated. Material and methods An ethanol extract of dried kudzu root was purified with an AB-8 resin column, and the concentrations of puerarin, daidzin and daidzein in the KUD were determined using UV spectroscopy. HUVECs were pretreated with various concentrations of the KUD with or without rotenone and the viability was assessed by AlamarBlue cell viability assay. Next, HUVECs were pretreated with the KUD and then treated with rotenone, and the levels of ROS generation, apoptosis, and changes of the mitochondrial membrane potential (ΔΨm) in HUVECs were measured using fluorescent staining assay and high-content analysis. Results The contents of three major isoflavonoids (puerarin, daidzin and daidzein) were enriched by 7.75–27.51 fold in the extract. The KUD enhanced the proliferation of HUVECs, and protected HUVECs against rotenone-induced oxidative stress and apoptosis. Additionally, the KUD prevented the loss of ΔΨm in HUVECs stimulated by oxidative stress. Conclusion We demonstrated that an isoflavonoid-rich extract prepared from kudzu root has the potential to act as a protector for vascular endothelial cells against intracellular ROS mediated apoptosis and mitochondrial damage. [ABSTRACT FROM AUTHOR]

The marked Mg segregation at grain boundaries (GBs) in nanocrystalline Al alloys usually contributes additional GB segregation strengthening. To gain a further understanding of this phenomenon, molecular dynamics simulations were conducted to reveal the Mg segregation behavior at Al Σ9 (221)[ 1 1 ¯ 0 ] symmetric tilt grain boundary (STGB) and its effects on the GB stability and strength. Results reveal that Mg dopants have a large driving force to segregate at Al GBs. Such Mg segregation not only enhances the strength of Σ9 (221) STGB but also improves GB stability. It is found that the Mg segregation turns to enlarge and narrow the strain intervals of stable and thickening stages of Σ9 (221) STGB during tensile test, indicative of the Mg-induced stabilizing effect on the GB structural integrity. Calculations further elucidate that the segregated Mg dopants increase the critical stress for dislocation nucleation, which accounts for the remarkably increased tensile strength of Σ9 (221) STGB with Mg segregation. Such retarded dislocation nucleation is ascribed to the decrement in boundary free volume by Mg segregation. This work will provide important atomic-scale insights into the extra GB strengthening in Al alloys deriving from Mg segregation. [ABSTRACT FROM AUTHOR]

Based on practical application requirements, the Cu alloy matrix with precipitates, particularly obstructing dislocation gliding, offers a promising pathway to substantially increase the strength of composites. Unfortunately, the fabrication of nano-precipitates often brings about extensive interface, which typically limits the electronic transmission capability and deteriorates the electrical conductivity. Herein, in-situ synthesized graphene nanoplatelets combined ball milling is deliberately selected to enable robust interfacial bonding and construct analogy-bicontinuous structures through hindering the diffusion of Ag in the Cu–Ag alloy matrix by the graphene nanoplatelets. The Cu alloy matrix composite after heat treatment exhibits a yield strength of ∼445 MPa and a fracture elongation of ∼13.5%, which is mainly ascribed to the introduction of the graphene nanoplatelets and the Ag nano-precipitates, and the adjustment of the analogy-bicontinuous structures. Meanwhile, the toughening mechanism of the Cu alloy matrix composite is rationalized on basis of delocalization and crack deflection affected by the graphene nanoplatelets and analogy-bicontinuous structures. Furthermore, the construction of continuous conductive path in the analogy-bicontinuous structures, refraining from the adverse effects caused by interface scattering, is of great benefit to the electrical conductivity, which is elevated to a high level of 92.2 IACS%. The present discoveries shed new insights into the innovative design of the Cu alloy matrix composites for advanced engineering applications by regulating the heterostructure. [Display omitted] • Analogy-bicontinuous structure was in situ synthesized with ball milling. • GNPs regulated the distribution of Ag nano-precipitates and electrical conductivity. • Synergy of mechanical properties and electrical conductivity was achieved. [ABSTRACT FROM AUTHOR]

For conversion type Li/Na-ion batteries anode materials, constructing the nanocomposite with enough interface interaction is of great importance for enhancing the electrochemical reaction kinetics and keeping the integrity of the electrode structure even after a long-term cycle at a high current density. In addition, the highly reversible conversion of discharge product also plays a vital role in prolonging the cycling life of conversion type anode materials for Li/Na-ion batteries. In this work, a composite of isolated ultrafine Fe 3 N nanocrystals (<15 nm) strongly coupled with N doped 3D porous carbon networks (N-3DPCN) were successfully fabricated via salt template-assisted calcination strategy. Both experimental results and theoretical simulations have validated that the powerful interface interaction between ultrafine Fe 3 N nanocrystals (<15 nm) and N-3DPCN is bound up with the N-doping in 3DPCN, and the atomically dispersed metal Fe in the N-3DPCN (SAFe-N@3DPCN) formed during the discharge process of Fe 3 N can catalyze the reversible conversion of discharge product Na 3 N. Benefited from these advantages, the as-constructed Fe 3 N@N-3DPCN composite delivers excellent Li/Na ion storage performance. This work shed light on the composite design of conversion-type materials and carbon materials for applications in energy storage fields and beyond. [Display omitted] • An effective synthesis strategy to improve the complex preparation process of Fe x N/C is proposed. • The interface coupling effect could enhance the interface interaction between ultrafine Fe 3 N nanocrystals and N-3DPCN. • The repetitive charge-discharge of Fe 3 N@N-3DPCN electrode could induce the in-situ formation of atomically dispersed Fe. [ABSTRACT FROM AUTHOR]

Bimetallic doping is widely used to enhance the oxygen evolution reaction (OER) activity of layered transition metal oxyhydroxides. However, the synergistic enhancement effect of different doping elements on the intrinsic OER activity is still obscure. In this study, the FeNi-codoped cobalt oxyhydroxide (CoOOH) as OER electrocatalyst was prepared successfully by simple electrodeposition and anodic oxidation methods, which exhibits superior OER activity to the single-metal doped CoOOH systems. Based on both experiments and first-principles calculations, the results show that the reaction kinetics enhance due to the codoping of Fe and Ni. Fe-doping changes the active site from Co to Fe and enhances the hydroxyl group adsorption. Ni doping benefits the electron transfer between Fe and intermediates, thereby enhancing the Fe–O covalent component to further balance the two steps of hydroxyl group adsorption and the deprotonation step. The essential mechanism of bimetal-doping in CoOOH provides theoretical support for the design and development of bimetal-doped Co-based OER catalysts. [Display omitted] • The FeNi-codoped CoOOH as OER electrocatalyst is prepared successfully, which has high OER activity and good stability. • Fe doping decreases the adsorption energies of intermediates and benefits adsorption between Fe and intermediates. • The increased covalent components between active sites and intermediates after Ni doping result in the enhanced OER activity. [ABSTRACT FROM AUTHOR]

In this study, ultralight monolithic silver foams were synthesized by a novel and easy method based on the traditional silver mirror reaction. The resultant silver foams had remarkably low densities down to 18.7 mg/cm 3 or 99.8% porosity. The compression properties were measured and the present ultralight silver foams showed a similar stress–strain behavior compared with the other metallic foams. The densification strain of the silver foam can reach 80% because of the ultralow density. The compressive stress increased with increasing relative density. [ABSTRACT FROM AUTHOR]

As one of the most efficient trace element to improve the mechanical properties of alloys, scandium (Sc) has attracted much attention for aluminum alloys in recent years. In this study, a new kind of Al–Zn–Mg–Cu–Sc–Zr alloy has been designed, and the evolution of microstructure and properties during the processes including homogenization, hot extrusion, solid solution and aging has been investigated. The alloy aged at 120 °C reveals a dual-peak aging phenomenon which is attributed to the overlap of the formation of Guinier–Preston (GP) zones and η′ phases. Consequently, excellent mechanical properties can be obtained (UTS = 747 MPa, YS = 721 MPa and EI = 10.9%) when the alloy is aged at 120 °C for 15 h. The improvement of the mechanical performance is mainly attributed to the grain refinement by the primary Al 3 (Sc, Zr) and the dispersion strengthening of the secondary Al 3 (Sc, Zr). Thus, the combined additions of Sc and Zr play an important role for the strengthening of the alloy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design strategies for 2D/2D NH 2 -TiO 2 /ReS 2 heterojunction photocatalyst. • The transition of NH 2 -TiO 2 /ReS 2 from type-Ⅰ to S-scheme heterojunction by amination modification. • An innovative construction engineering for 2D/2D heterojunction The 2D/2D heterojunction photocatalyst demonstrates a broad range of applications owing to its large interface contact area. At present, most of the current 2D/2D structures are constructed by self-assembly, which mainly forms a relatively weak van der Waals force at the interface. This poses a challenge to achieving effective carrier separation. Here, we proposed an innovative strategy of molecular-connected heterojunctions to address this challenge. The strategy uses (3-aminopropyl) trimethoxysilane (APTMS) to modify the surface of TiO 2 and construct NH 2 -TiO 2 /ReS 2 heterojunction, which not only alters the material's Zeta potential but also uses molecular chains connecting TiO 2 and ReS 2. Simultaneously, the design of molecular-connected heterojunction changes the work function of TiO 2 , leading to the transformation of the TiO 2 /ReS 2 heterojunction from type-Ⅰ to S-scheme, thereby achieving a selective carrier separation. The constructed NH 2 -TiO 2 /ReS 2 photocatalytic heterojunction composite has a hydrogen production rate of 451.3 μmol g-1 h−1, which is over 11 and 3 times than TiO 2 and TiO 2 /ReS 2 , respectively, and exhibits excellent long-term photocatalytic stability. This study presents a novel approach for achieving strong interface bonding and introduces an innovative approach for constructing 2D/2D photocatalytic heterojunctions. [ABSTRACT FROM AUTHOR]

Al–Mg-oxides composite system exhibits great potential for achieving aluminum matrix composites (AMCs) with exceptional mechanical properties. However, the effects of Mg element on in-situ reaction mechanism and precipitation behavior remains largely unknown. In this work, Al–Mg–ZnO composite was successfully fabricated by using segmented ball milling, reaction sintering and heat treatment, resulting in an ultimate tensile strength of ∼760 MPa and fracture elongation of ∼3.5 %. The Mg content-dependent reaction pathway and precipitation evolution were systematically investigated through thermodynamic analysis and microstructural characterization. The results revealed that the relatively high Mg content promotes the in-situ generation of the hybrid reinforcements composed of MgAl 2 O 4 and MgO. Additionally, the semi-coherent reinforcement-matrix interface facilitates interfacial precipitation by reducing the energy barrier for nucleation. Consequently, solute-rich/vacancy-rich Guinier-Preston (GP) zones are activated to form η′ and T′ precipitates. These high-density nano-sized secondary phases contribute to the considerable strengthening effect of the composite. The present work provides valuable theoretical insight into the effect of Mg content on the microstructure evolution of Al–Mg–ZnO composite system, which offers promising avenues for achieving AMCs with superior mechanical properties. • Al–Mg–ZnO composites were in-situ synthesized using segment ball-milling (SBM) combined with reaction sintering. • Mg content dependence of the in-situ reaction path was systematically investigated by microstructural characterization. • Changes in Mg content cause competition in precipitation mechanisms of the different kinds of Guinier-Preston (GP) zones. • Reinforcement-Al interface and secondary phases account for the exceptional mechanical properties of the Al–Mg–ZnO composite. [ABSTRACT FROM AUTHOR]

The Li–CO2 battery often suffers from high overpotential and limited capacity due to the challenges associated with the adsorption of Li+ and CO2 and the decomposition of Li2CO3. Herein, hexagonal rich-stepped NiSe crystals are in situ achieved on a three-dimensional (3D) free-standing porous Ni skeleton with double continuous channel architecture (namely p-Ni@NiSe-50) through an in situ selenization process. Structural characterization and theoretical calculation are applied to demonstrate the synergistic effects of marco/microstructural design and electronic band structure regulation. As a result, the adsorption/desorption of Li+ and CO2 and the formation/decomposition of Li2CO3 are effectively promoted, simultaneously, enabling an enhanced capacity and reversibility of p-Ni@NiSe-50 as the cathode of Li–CO2 battery. An ultra-low overpotential of 0.46 V and a remarkably high energy efficiency of 83.8% (20 μA cm−2) are achieved, along with a high full discharge specific capacity of 8844 μAh cm−2. Excellent long-term cycling stability (cycles up to 1000 h at a voltage gap of 1.14 V) of p-Ni@NiSe-50 is also obtained. The results of this work would provide a new insight and strategy to develop high-performance alkali metal-air batteries.Multi-scale synergistic effect of combining the cathode macroscopic structure design and the microscopic band structure design of NiSe was demonstrated to promote the adsorption of Li+ and CO2, as well as the decomposition of Li2CO3, so as to achieve ultra-low voltage gap and high capacity of Li-CO2 batteries.Graphical abstract: The Li–CO2 battery often suffers from high overpotential and limited capacity due to the challenges associated with the adsorption of Li+ and CO2 and the decomposition of Li2CO3. Herein, hexagonal rich-stepped NiSe crystals are in situ achieved on a three-dimensional (3D) free-standing porous Ni skeleton with double continuous channel architecture (namely p-Ni@NiSe-50) through an in situ selenization process. Structural characterization and theoretical calculation are applied to demonstrate the synergistic effects of marco/microstructural design and electronic band structure regulation. As a result, the adsorption/desorption of Li+ and CO2 and the formation/decomposition of Li2CO3 are effectively promoted, simultaneously, enabling an enhanced capacity and reversibility of p-Ni@NiSe-50 as the cathode of Li–CO2 battery. An ultra-low overpotential of 0.46 V and a remarkably high energy efficiency of 83.8% (20 μA cm−2) are achieved, along with a high full discharge specific capacity of 8844 μAh cm−2. Excellent long-term cycling stability (cycles up to 1000 h at a voltage gap of 1.14 V) of p-Ni@NiSe-50 is also obtained. The results of this work would provide a new insight and strategy to develop high-performance alkali metal-air batteries.Multi-scale synergistic effect of combining the cathode macroscopic structure design and the microscopic band structure design of NiSe was demonstrated to promote the adsorption of Li+ and CO2, as well as the decomposition of Li2CO3, so as to achieve ultra-low voltage gap and high capacity of Li-CO2 batteries. [ABSTRACT FROM AUTHOR]

Elucidation of the relationship among crystal structure, material compositions, and electrocatalytic performance is beneficial to the design of electrocatalysts with high activity. Specially, for bifunctional electrocatalysts, there is a lack of the unified understanding of oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) mechanisms. Based on the first-principles calculations, LaCoO 3 surface reconstructions with different OH coverage under OER/ORR condition are determined. Thereby, the different reaction pathways for OER and ORR with the cooperation of Co and O sites are revealed, under which Co and lattice O sites are activated dynamically, and an overpotential of 0.35 V for the OER and 0.44 V for the ORR are obtained. Furthermore, the octahedra lattice distortion-related bifunctional mechanism (DRBM) is proposed from electron structure analysis, and the bifunctional activity of different B-site doped LaCoO 3 (LaCoMO 3) are studied. Based on this mechanism, we find that OER, ORR, and their bifunctional activity of LaCoMO 3 all exhibit a volcano trend as a function of the O-B-O bond angle formed by Co and lattice oxygen. Consequently, we predict that Mn, Cr, Fe, and Ti doped LaCoO 3 electrocatalysts exhibit remarkable bifunctional activity, which is corroborated by the reported experimental results. This is special type of abstract that is so short and could be inserted after main abstract of article, as a blurb or inserted as annotations into a Table of contents [Display omitted] [ABSTRACT FROM AUTHOR]

The segregation of alien solute atoms at grain boundaries (GBs) in nanocrystalline materials can dramatically affect their macroscopic properties. As important solutes in Al alloys, Mg and Cu atoms have been experimentally observed to segregate at GBs, which would render a significant impact on the material. In this work, first-principles calculations were used to conduct a systematic and comprehensive investigation to reveal the segregation behavior of Mg and Cu atoms at Al Σ5 (310) and Σ9 (221) GBs and its effect on GB properties. The negative segregation energy demonstrates that both Mg and Cu have a strong tendency to segregate to the Al GBs. Moreover, the segregation of Mg and Cu atoms can reduce the GB energy, indicating an increased thermodynamic stability of the GBs. Mechanical properties are explored by a combination of canonical Griffith fracture model with ab-initio tensile test method. Results reveal that the doped Mg will embrittle both GBs due to the elongation of interatomic bonds and depletion of charge density across the GBs. Contrarily, the segregated Cu contributes greatly to enhancing the GB strength by creating strong Cu-Al bonds with surrounding Al at GBs. Besides, the increased tensile separation displacement of GBs with Cu segregation also suggests an improved resistance to fracture, especially the Σ9 (221) GB. This work provides a theoretical understanding for the changes in microscopic properties of Al GBs caused by Mg and Cu segregation from an atomic and electronic level. [Display omitted] • Mg/Cu solutes have strong segregation tendency toward Ʃ5 (310) and Ʃ9 (221) GBs in Al alloys. • Mg/Cu segregation thermodynamically stabilizes the Ʃ5 (310) and Ʃ9 (221) GBs. • Mg doping causes embrittlement of Al GBs while Cu segregation will enhance the GB cohesion. [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]

Due to the poor compatibility between the reinforcement and Cu matrix, interfacial bonding is of vital importance for the comprehensive properties of graphene nanoplatelets (GNPs)/Cu matrix composites. Herein, we reported a novel hybrid reinforcement with pea-pod structure (surface protruding structure of GNPs) prepared via in situ synthesis, which contributed to the dramatically ameliorated interfacial structure of the composites and regulated the quasi-stability deformation process. The Cu@GNPs@Al 2 O 3 /Cu composite exhibited optimal strength (YS: 290 MPa-0.45 vol% Al 2 O 3 , 300 MPa-0.76 vol% Al 2 O 3), moderate ductility (18%), as well as far exceeding the toughness of the GNPs/Cu composites. Concurrently, the electrical conductivity of the composite remains at a high level of 96.5 IACS%. The present findings may provide a feasible strategy to optimize interfacial structure by adjusting the structure of reinforcement, which enables improved comprehensive properties of the Cu matrix. [Display omitted] • Hybrid reinforcement with pea-pod structure was prepared via in situ synthesis. • Surface protrusion of GNPs ameliorates interfacial structure of the composites. • Cu composites have better mechanical properties and electrical conductivity. [ABSTRACT FROM AUTHOR]