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The quality of economic development is not sufficient, despite the apparent role that public environmental monitoring and management play in the economy's rapid expansion. Therefore, enhancing the standard of economic growth is of the utmost importance. It is vital to establish innovative management techniques to support social and governmental transformation in order to raise the standard of economic development. Economic development affects public administration's fundamental duties and goals. The division of public administration distributes social resources and enhances the market's function. The fundamental problem in public economic management is how to successfully actualize rational resource allocation, advance social justice, and boost social welfare on the basis of resource scarcity and the breakdown of the market mechanism. This study greatly increases the global optimization performance of the fundamental ant colony method and provides the explicit programme and simulation stages for the new algorithm. Finally, simulation tests are conducted using the basic ant colony algorithm and the upgraded ant colony algorithm in relation to the decision-making model of public economic management. According to the simulation findings, the revised algorithm successfully addresses the traditional approach's drawbacks, including its slow convergence speed and propensity to easily enter local minima, and its optimization performance has increased by 30.23%. [ABSTRACT FROM AUTHOR]

Abstract To limit the pulverization of tin-based anode materials during lithiation/delithiation, submicron tin oxide/tin particles are fixed on core/sheath carbon nanofiber/spongy carbon via hydrothermal and carbothermal reduction treatment in this work. During carbothermal reduction, SnO 2 nanosheets are converted to spherical Sn submicron particles and simultaneously the hollow spongy carbon is produced and still enwrap on carbon nanofiber. The as-produced flexible film is used for a binder-free anode for lithium ion batteries, without the polymer binder and conductive carbon. At 0.1, 0.5, 1 and 2 A g−1, the composite electrode respectively displays a discharging capacity of 1393.0, 738.2, 583.6 and 382.6 mAh g−1. Moreover, it delivers specific capacity of 726.9 mAh g−1 and coulombic efficiency of 99.45% after 300 cycles at 0.1 A g−1. The comparison sample of carbon nanofiber/SnO x film without the presence of spongy carbon displays much lower rate performance and worse cyclic performance. The integrated structure of carbon nanofiber/SnO x /spongy carbon results in the remarkable Li-storage performance, in which the carbon nanofiber and spongy carbon synergistically provide conductive channel and buffer zone to hinder the pulverization and peeling of SnO x particles during charging-discharging processes. Graphical abstract Image 1 Highlights • Submicron SnO 2 particles fixed on core/sheath carbon nanofibers/spongy carbon. • CNF/SnO x /SC flexible film used as a binder free anode material. • SnO 2 nanoflakes coated by spongy carbon can be reduced to Sn submicron particles. • Integrated CNF/SnO x /SC provides conductive channel and buffers volume change. [ABSTRACT FROM AUTHOR]

3D nanohybrid structures with few-layered MoS2 nanosheets uniformly incorporated in the carbon substrate are prepared via using the rapid and homogeneous microwave-hydrothermal method, in which the size of the basic unit structure of MoS2/C was small. The samples were systematically investigated by X-ray diffraction, field emission scanning electron microscopy, X-Ray photoelectron spectroscopy and high-resolution transmission electron microscopy for structure and composition test. The electrochemical performances of the composites are evaluated by cyclic voltammogram, galvanostatic charge-discharge and electrochemical impedance spectroscopy. Electrochemical measurements reveal that the maximum-specific capacitance of the MoS2/C electrodes reaches up to 1003 mAh g-1 at a discharge current density 100 mA g-1. The MoS2/C hybrid composite remains 755 mAh g-1 after 50 cycles at the current of 200 mA g-1, much higher than that of the pure MoS2. The superior electrochemical performances of MoS2/C composites as Li-ion battery anodes are attributed to their enhanced available active sites for charges, decreased transmission resistance between interlayers, improved electronic conductivity as well as good mechanical stability. [ABSTRACT FROM AUTHOR]

A novel approach for hierarchically porous S-doped carbon was developed. Owing to the obviously reduced particle size and greatly enhanced meso-/macropores, electronic conductivity and surface polarity as well as the active sites available for Faradaic reactions, the resultant S-doped carbon electrode shows an excellent supercapacitor performance. [ABSTRACT FROM AUTHOR]

This work presents a design of sandwich MoO3/C hybrid nanostructure via calcination of the dodecylamine-intercalated layered α-MoO3, leading to the in situ production of the interlayered graphene layer. The sample with a high degree of graphitization of graphene layer and more interlayered void region exhibits the most outstanding energy storage performance. The obtained material is capable of delivering a high specific capacitance of 331 F g−1 at a current density of 1 A g−1 and retained 71% capacitance at 10 A g−1. In addition, nearly no discharge capacity decay between 1000 and 10 000 continuous charge-discharge cycles is observed at a high current density of 10 A g−1, indicating an excellent specific capacitance retention ability. The exceptional rate capability endows the electrode with a high energy density of 41.2 W h kg−1 and a high power density of 12.0 kW kg−1 simultaneously. The excellent performance is attributed to the sandwich hybrid nanostructure of MoO3/C with broad ion diffusion pathway, low charge-transfer resistance, and robust structure at high current density for long-time cycling. The present work provides an insight into the fabrication of novel electrode materials with both enhanced rate capability and cyclability for potential use in supercapacitor and other energy storage devices. [ABSTRACT FROM AUTHOR]

In the past few years, internet celebrities have become a new and important way to get people to buy energy-saving products. Their psychological mechanisms for promoting fans' intention to purchase have become the focus of academic attention, but a unified conclusion has yet to be reached. This study uses online communities as a scenario, with the characteristics of influencers' expertise, social attraction, and task attraction as antecedent variables and social cognitive theory and parasocial interaction theory as the theoretical basis to explore their influence on fans' intention to purchase household energy-saving products. The study investigates the mediating role of parasocial relationships and the moderating role of fans' green self-efficacy in influencing internet celebrities' expertise and attraction of fans' parasocial relationships. The results showed that the parasocial relationships formed between fans and influencers mediated the relationship between the expertise and attraction of influencers and fans' intention to purchase energy-saving products and that "green self-efficacy" positively moderated the parasocial relationships formed between fans and internet celebrities in terms of their expertise and task attraction. The moderating effect of "green self-efficacy" on the parasocial relationships between fans and internet celebrities was insignificant. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report the sphere-like C/CuO and CuO nanocrystals that have been fast prepared by the microwave-assisted hydrothermal method in the presence of green additive d-glucose. The rapid formation mechanism of the C/CuO and CuO nanocrystals and how the d-glucose worked in the microwave-assisted hydrothermal system were discussed in details. The crystal phase, morphology and electrochemical performance were characterized by means of X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM) and electrochemical testing. The XRD patterns indicated that the CuO nanocrystals are pure with monoclinic structure and TEM images showed that the size of the samples could be tunable by adjusting the ratio of d-glucose and metal salt. Finally, a possible growth mechanism for the C/CuO spheres and CuO nanocrystals was proposed and discussed. The electrochemical performance of the products may be influenced by the size and uniformity of the nanocrystals. [Copyright &y& Elsevier]

Abstract: Olivine structure LiMnPO4 has been considered as one of the very promising electrodes for lithium-ion batteries because of their low cost, low toxicity and high voltage plateau compared with LiFePO4. In order to improve the electrochemical performance a key challenge in the field of lithium-ion battery, is to explore and invent suitable synthetic route to control the size and morphology of LiMnPO4. Here a detailed study exploring the novel route of microwave-hydrothermal (MH) synthesis for successfully obtaining LiMnPO4 crystals within few minutes is reported and the reaction process discussed in detail. Variation of the synthetic parameters show that a decrease in reactant concentration could lead to LiMnPO4 nano-platelets orientated in the ac plane with a very high electrochemical performance. The effect of the starting precursor (like, Mn) concentration as a means to tailor LiMnPO4 electrochemical performance is discussed. The effect of alteration of size, morphology, lattice parameters and crystal structure induced by addition of additives like citric acid (H3cit) and sodium dodecyl benzene sulfonate (SDBS) is further described and an example of the first reversible discharge of a product treated with H3cit obtained by MH route as high as 89.0mAh/g, is shown. The general investigation demonstrates that there is a relationship among microwave irradiation condition, crystal structure, morphology and electrochemical performance that can be exploited for the design of next generation lithium batteries. [Copyright &y& Elsevier]

Abstract: To investigate the crystal structure and electrochemical performance of samples synthesized under different microwave solid-state synthesis condition, a series of Li3V2(PO4)3 samples has been synthesized at five different temperatures for 3–5min and at 750°C for various time. The as-synthesized Li3V2(PO4)3 samples are characterized and studied by ICP-AES analysis, X-ray diffraction (XRD), Rietveld analysis, scanning and transmission electron microcopy (SEM and TEM). At relatively lower temperature (650°C) and very short reaction time (3min), pure phase of Li3V2(PO4)3 could be synthesized in microwave irradiation field. The crystal structure and Li atomic fractional coordinate present a significant deviation upon the change of microwave irradiation temperature and time. Relatively, the diffusion ability of lithium cations and the electrochemical performance are affected. Under the proper reaction temperature and time, the carbon-free samples MW750C5m and MW850C3m show the best specific discharge capacity 126.4 and 132mAhg−1 at the voltage range of 3.0–4.3V, near the reversible cycling of two lithium ions per Li3V2(PO4)3 formula unit (133mAhg−1). At the voltage range of 3–4.8V, the sample MW750C5m presents the best initial specific charge capacity of 197mAhg−1, equivalent to the reversible cycling of three lithium ions per Li3V2(PO4)3 formula unit (197mAhg−1). The initial discharge capacity, the samples MW750C5m and MW850C3m present high specific discharge capacity 183.4 and 175.7mAhg−1, respectively. The relationship among microwave irradiation condition, crystal structure, lithium atomic fractional coordinates and the electrochemical performance have been discussed in detail. [Copyright &y& Elsevier]

Abstract: Rod-like orthorhombic LiMnO2 nanocrystals were successfully synthesized using temperature-controlled microwave hydrothermal route (TCMH) in a short time (30min) at a temperature as low as 160°C. o-LiMnO2 obtained by two different methods was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemistry test. SEM revealed that the product obtained in case of TCMH was rod-like with a diameter of 40nm, while the nanoparticles with 200nm diameter were obtained by traditional hydrothermal route (TH). The dramatic formation of o-LiMnO2 in the microwave hydrothermal field influenced the morphology and crystal structure of the final products. The formation and preferred growth orientation mechanism of o-LiMnO2 in the microwave irradiation process was discussed. Electrochemistry performance exhibited that the as-synthesized o-LiMnO2 nanorods reached the maximum discharge capacity of 194.2mAhg−1 at 0.1C rate after several cycles between 2.2 and 4.4V vs. Li+/Li at room temperature, which was higher than the electrochemical performance of o-LiMnO2 obtained by TH. The experimental results showed that the TCMH method provided an effective way for preparing o-LiMnO2 cathode material in lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: Vanadium (V) was used as the central heteroatom in the synthesis of the Keggin-type polyoxometalate {[CH3(CH2)7]4N}3[VMo12O40] (1). This compound was characterized by elemental analysis and single-crystal X-ray diffraction. Compound 1 was used as a bulk-modifier to fabricate the chemically modified ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) carbon paste electrode (1-ILCPE) by direct mixing. The bulk-modified 1-ILCPE showed well-defined cyclic voltammograms with four reversible redox couples in H2SO4 +Na2SO4. The first wave could be ascribed to the reduction of the central V and the last three waves corresponded to the redox processes of the peripheral Mo atoms. The 1-ILCPE presents good electro-catalytic activity not only toward the oxidation of l-cysteine, which is attributed to the function of the central V, but also toward the reduction of hydrogen peroxide, which is attributed to the function of the Mo atoms. Compared with the conventional carbon paste electrode (CPE), the excellent experimental results suggest that the newly developed paste electrode holds great promise in the design of electrochemical devices, such as sensors and biosensors. The promising results are ascribed to the use of an ionic liquid, which forms an excellent charge-transfer bridge and wide electrochemical windows in the bulk of carbon paste electrode. [Copyright &y& Elsevier]

Abstract: Shape-controlled synthesis of CuS nanorods, nanoflakes, and flowerlike structures has been achieved simply in the presence of a nonionic surfactant polyethylene glycol (PEG20000) by adjusting hydrothermal temperature. The as-synthesized CuS nanocrystals were investigated by various techniques of XRD, TEM, SEM, and UV–vis spectra. The electron diffraction pattern indicated that the CuS nanoflakes were single crystals. In the process, the temperature and the surfactant PEG20000 were found to play important roles in determining the morphology of CuS nanocrystals. [Copyright &y& Elsevier]

Abstract: By employing sodium dodecyl sulfate as the templating agent, mesoporous lanthanum oxide/surfactant complexes of hexagonal and lamellar phases were synthesized within the micellar solution of various pH values. The structures of the resulting products were studied by XRD, HRTEM, SEM and TG/DTA. The XRD patterns and HRTEM micrographs showed that the interlayer distance of the typical lamellar structure products was ranging from 3.5 to 4.0 nm and the unit cell parameter of the produced ordered hexagonal structures was about 4.4 nm. [Copyright &y& Elsevier]

This work successfully prepared homogeneous heterostructure nanocomposites comprised of few-layered MoO 3 and graphite nanosheets (MoO 3 /C) on a large scale via a ball-milling method with bulk MoO 3 and expandable graphite as raw materials. The shear and impact forces generated by the agate balls with a diameter of 2 mm can present the most ideal synergistic effect to strip the MoO 3 nanosheets from its mother body with a small size and thickness. The obtained MoO 3 nanosheets are distributed homogeneously on the surface of carbon nanosheets (<10 layers), providing many Li-storage sites and stable structure during the charging-discharging process. Hence, the obtained electrode material shows the high rate performance (817 mAh g−1@1000 mA g−1) and stable cycle performance (810 mAh g−1 after 70 cycles@200 mA g−1). More importantly, we basically understand the functional rule about the effects of the size of the agate balls on ball-milling efficiency for two kinds of layered materials. A ball-milling approach was used to in-situ peel bulk MoO 3 and expanded graphite to prepare massive homogeneously heterostructure nanocomposites comprised with few-layered MoO 3 and graphite nanosheets (MoO 3 /C) with enhanced electrochemical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Natural structural materials with intricate hierarchical architectures over several length scales exhibit excellent combinations of strength and toughness. Here we report the mechanical response of a crossed-lamellar structure in Cymbiola nobilis shell via stepwise compression tests, focusing on toughening mechanisms. At the lower loads microcracking is developed in the stacked direction, and channel cracking along with uncracked-ligament bridging and aragonite fiber bridging occurs in the tiled direction. At the higher loads the main mechanisms involve cracking deflection in the bridging lamellae in the tiled direction alongside step-like cracking in the stacked direction. A distinctive crack deflection in the form of 'convex' paths occurs in alternative lamellae with respect to the channel cracks in the tiled direction. Furthermore, a barb-like interlocking mechanism along with the uneven interfaces in the 1st-order aragonite lamellae is also observed. The unique arrangement of the crossed-lamellar structure provides multiple interfaces which result in a complicated stress field ahead of the crack tip, hence increasing the toughness of shell. [ABSTRACT FROM AUTHOR]

Three dimensional networks, herein carbon coated SnO 2 micron-sized particles are fixed in carbon nanofibers (CNF/SnO 2 @C), is fabricated and synthesized by using hydrothermal method and carbonization. The weight ratio of SnO 2 reaches to 50% of CNF/SnO 2 @C, meanwhile, CNF/SnO 2 @C remains its flexibility. CNF/SnO 2 @C film is directly used as a binder-free anode for lithium ion batteries without conductive additive and polymer binder. The discharge capacities of CNF/SnO 2 @C are 1286 mAh g −1 at 0.05 A g −1 and 397 mAh g −1 at 1 A g −1 , respectively. The buffering effect of CNFs is studied by using ex-situ SEM in the cycled electrodes operated at various lithiation states. The particles size of SnO 2 @C sample increase to 4 μm after 20 charge/discharge cycles, and a serious aggregation of particles occurs in the cycled SnO 2 @C electrode which is in coincidence with its rapidly faded capacity. The particles of CNF/SnO 2 @C sample also present the increased size from the original size of 2 μm to the lithiated size of 4 μm but they are still fixed in CNFs network without any aggregation. The improved specific capacity, cyclic stability and rate performance of CNF/SnO 2 @C are attributed to the structural synergy of CNFs and SnO2 particles, because CNFs as flexible substrate provides excellent conductive channel improving the rate capability and effective network buffering the volume change to promote the cyclic performance. [ABSTRACT FROM AUTHOR]

Ion crystal ammonium tetrathiomolybdateas (NH 4) 2 MoS 4 with the octahedral structure and high hardness could efficiently transfer and magnify the impacting and shearing force generated from ball-milling process to the surface of expandable graphite (EG) to accelerate its exfoliation and fragmentation. The obtained massive precursor comprised of nano-(NH 4) 2 MoS 4 and carbon nanosheets with few layers could transfer into MoS 2 /C sandwiched nanocomposites after subsequent calcination, which owns satisfied Li-storage performance even at relatively high current density. [Display omitted] • Ion crystal (NH 4) 2 MoS 4 could efficiently transfer and magnify the impacting and shearing force because of its octahedral structure and high hardness. • EG was exfoliated effectively with the assistance of (NH 4) 2 MoS 4 and obtain massive few-layered MoS 2 /C nanocomposites. • The novel heterostructure serves many active sites and stable structure for storing Li-ions. • The obtained electrode material is with a high rate and stable cycle performance. Ball milling has been proven to be an efficient method for exfoliating and reassembling heterogeneous layered nanocomposites on a large scale. This study explores the use of ammonium tetrathiomolybdate (NH 4) 2 MoS 4 , an ion crystal with an octahedral structure, as both a precursor of layered molybdenum disulfide (MoS 2) and an intermediate during ball milling to assist in the exfoliation and fragilization of expandable graphite (EG). Due to its ion crystal structure and high hardness, (NH 4) 2 MoS 4 can efficiently transfer and magnify the impacting and shearing forces generated during the ball milling process, accelerating the exfoliation and fragmentation efficiency of EG. Moreover, (NH 4) 2 MoS 4 is nano-crystallized by the ball milling forces and uniformly distributed on the carbon nanosheets. Electrochemical performance tests indicate that the resulting nanocomposites, with a satisfactory heterogeneous structure, exhibit excellent Li-storage capacity, achieving 529 mA h g−1 after 150 cycles at a high current density of 500 mA g−1. The relationship between the microstructure and improved electrochemical performance, as well as the formation mechanism of the product, is discussed in detail. This study provides a new approach for conveniently constructing nanocomposites using two types of layered materials that offer satisfactory rate capability and cyclability, making them potentially suitable for application in Li-ion batteries. [ABSTRACT FROM AUTHOR]

• Heat treatments have a negative impact on indentation properties of crossed-lamellar structure. • The hardness has a significantly positive correlation with the interface bonding strength. • The indentation recovery phenomenon mainly depends on the viscoelasticity of organic matrix. Mollusk shells are known for their excellent mechanical properties from the complex hierarchical microstructures consisting of calcium carbonate and a small quantity of organic matrix. To investigate the influence of the adhesive organic matrix on the microscopic indentation properties of crossed-lamellar structure in the Cymbiola nobilis (C. nobilis) shell, Vicker's indentation tests were performed on the specimens with different states (wet, fresh, and calcined at 180°C and 300°C). It is found that the hardness of specimens decreases in this order, which is mainly attributed to the decreased interface bonding strength induced by the loss of moisture and the melting of organic matrix with increasing heat-treatment temperature. Additionally, the indentations of WET, RT and 180°C specimens show a partial recovery with extending time of repose, reflecting a characteristic of viscoelasticity. There is no recovery in 300°C specimen since the molten organic matrix loses its elasticity. The effects of organic matrix on the hardness and indentation recovery behavior of different specimens come from the changes in its elasticity and the interface bonding strength. [ABSTRACT FROM AUTHOR]

Summary: Although the high‐capacity Si/graphite anode serves to advance the energy density of lithium‐ion batteries, the volume change remains the main disfigurement of Si/graphite anode. Many studies show that crosslinked structure binders tend to play a good inhibitory effect on volume expansion. In this work, a three‐dimensionally covalently cross‐linked and flexible polyimides (C–PI–OH) is successfully synthesized and applied as silicon/graphite anode, which is composed through a tri‐monomer co‐polycondensation and crosslinking process. The as‐formed free carboxylic acid groups and amide groups in C–PI–OH are efficient in structural stability, so the electrode bound by C–PI–OH exhibits the highest peeling strength than C–PI and polyvinylidene fluoride. The flexible network of the C–PI–OH binder is competent for accommodating the volume expansion and contraction of silicon particles during the deintercalation of lithium ion, which helps in the wholeness of solid electrolyte interface film and electrodes, and effectively boosting the cycle stability of the Si/graphite anode. [ABSTRACT FROM AUTHOR]

The correlation between the internal calice arrangement and compressive behavior of the skeleton of coral Pocillopora verrucosa has been characterized. The internal calices of this skeleton are arranged radially from a central axis in each branch. Such an arrangement of the calices results in a gradient distribution of the compressive properties; the middle part provides a higher strength, and the marginal part of the coral branch can undergo larger deformation to a certain extent. That is to say, the coral skeleton can offer a stronger internal support and a tougher external layer. Thus, the coral skeleton, as a natural porous and mineral material, can effectively undergo the ocean currents and provides a sturdy framework to protect the living polyps. [ABSTRACT FROM AUTHOR]

A series of composites manganese oxide/carbon with one-dimensional structure are synthesized using electrospinning. The phase composition, morphology and electrochemical performance of MnO x /carbon are studied, which affected by the manganese concentration in precursor and subsequent carbonization conditions. The manufacture of MnO x /carbon is composed of two steps including thermal stabilization (at 250 °C in air) and carbonization (at 700 °C in nitrogen). The main functional groups of samples are well identified by FT-IR spectra. The sample Mn33_3h with the lowest manganese content presents the construction structure which amorphous and/or nanosized MnO x with smaller crystal size are grown and enwrapped in carbon fiber during carbonization. Mn33_3h presents the initial charge and discharge capacities of 1054.1 and 665.6 mAh g−1, and the discharge capacity at the 50th cycle remains 99.7% of that at the 2nd cycle. Beside the well rate capability at the range of current densities from 20 to 1000 mA g−1, Mn33_3h presents very good recovery ability after high rate cycling at 1000 mA g−1. The advantages of this composite structure as well as its high capacity make manganese oxide a very attractive candidate as an anode material for the next generation of rechargeable lithium ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Monoclinic Li3V2(PO4)3 can be rapidly synthesized at 750°C for 5min (MW5m) by using temperature-controlled microwave solid-state synthesis method (TCMS). The carbon-free sample MW5m presents well electrochemical properties. In the cut-off voltage 3.0–4.3, MW5m presents a charge capacity 132mAhg−1, almost equivalent to the reversible cycling of two lithium ions per Li3V2(PO4)3 formula unit (133mAhg−1), and discharge capacity 126.4mAhg−1. In the cut-off voltage 3.0–4.8V, MW5m shows an initial discharge capacity of 183.4mAhg−1, near to the theoretical discharge capacity. In the cycle performance, the capacity fade of Li3V2(PO4)3 is dependent on the cut-off voltage and the preparation method. [Copyright &y& Elsevier]

Abstract: Monoclinic Li3V2(PO4)3 can be rapidly synthesized at 750°C for 5min (MW5m) by using microwave solid-state synthesis method. The refined cell parameters and atomic coordination of the sample MW5m show some deviations compared with those of the sample synthesized in conventional solid-state synthesis method, especially the coordinate of Li atoms. Compared with the electrochemical properties of the carbon-coating sample Li3V2(PO4)3, the carbon-free sample MW5m presents well electrochemical properties. In the cut-off voltage of 3.0–4.3V, MW5m sample presents a specific charge capacity of 132mAhg−1, almost equivalent to the reversible cycling of two lithium ions per Li3V2(PO4)3 formula unit (133mAhg−1), and specific discharge capacity of 126.4mAhg−1. In the cut-off voltage of 3.0–4.8V, MW5m shows an initial specific discharge capacity of 183.4mAhg−1 at 0.1C, near the theoretical discharge capacity. In the cycle performance, the capacity fade of Li3V2(PO4)3 is dependent on the cut-off voltage and the preparation method, more capacity lost at relatively higher charge/discharge voltage. The reasons for the excellent electrochemical properties of Li3V2(PO4)3 rapidly synthesized in microwave field are discussed in detail. [Copyright &y& Elsevier]

We made photonic crystals composed of artificial opals infiltrated with ZnS semiconductor nanocrystals by using self-assembly and solvothermal methods. SEM images show that the silica spheres exhibit a well-ordered arrangement and the ZnS nanocrystals infiltrate within the opal templates by heterogeneous nucleation and growth processing, and the as-synthesized ZnS nanocrystals reveal a cubic phase from X-ray diffraction pattern. Furthermore, the optical properties of the infiltrated opals with different ZnS filling ratio are also studied by transmission spectroscopy, respectively. It is proposed that the position of the stop band can be easily designed by controlling the infiltration ratio of ZnS. These results demonstrate an easy-to-handle and efficient route to obtain high performance photonic crystal structures. [Copyright &y& Elsevier]

• The samples exhibit higher strength and toughness at θ = 0° or 90°. • The strength and fracture toughness show positive relationship with vessel area. • Vessels can effectively arrest crack propagation at θ = 90°. Balsa wood, as one of the lightest woods available, presents superior mechanical properties, and thus it is one of the most appealing core materials particularly for marine and aerospace applications. However, the strengthening and toughening mechanisms in balsa wood are still poorly understood. The present work indicates that the samples exhibit higher strength and toughness concurrently, provided the loading direction is perpendicular to rays; in this case, vessels with strong walls can provide mechanical support, blunt cracking and stop horizontal cracking, and rays can arrest axial cracking. The present research findings are expected to provide fundamental insight into the design of high-performance bionic materials with a highly fibrous and porous structure. [ABSTRACT FROM AUTHOR]

Manganese oxides (MnOx) as potential anode materials need support by porous carbonaceous materials to avoid its large volume change, pulverization and poor conductivity during lithiation and delithiation. However, the homogeneous distribution of MnOx particles onto graphene sheets (rGO) is still questionable, because both components have different densities and activity in solution. Freeze-drying technique has gained remarkable attention for the fabrication of porous nanocomposites. In this work, a homogeneous nanocomposite of MnOx/rGO is successfully synthesized by freeze-drying technique compared with MnOx/rGO sample synthesized by traditional drying method, and MnrGO-FD sample exhibits an improved rate performance and cyclic performance. It delivers 1446.4 mAh g−1 with Coulombic efficiency (CE) of 70.4% at the initial cycle and remains 1246.6 mAh g−1 with CE of 98.6% after 150 cycles at 0.1 A g−1. Moreover, it delivers capacity of 729.1 mAh g−1 with CE of 99.3% at 1 A g−1 for 300 cycles. Benefiting from freeze-drying, MnOx nanoparticles are distributed on porous graphene framework and graphene buffers the volume expansion of MnOx and provides conductive channels between electrolyte and active materials. [ABSTRACT FROM AUTHOR]

Summary: The heterostructural construction of metal disulfide/oxide is essential in the electrochemical performance as anode material for lithium‐ and sodium‐ion batteries (LIBs and SIBs). In this work, an integrated composite of molybdenum disulfide (MoS2) and hexagonal molybdenum dioxide (MoO2) together enwrapped in reduced graphene oxide (rGO) is synthesized under hydrothermal condition. In the pelletizing MoS2‐MoO2/rGO composite, rGO as substrate effectively prevents the restacking and pulverization of MoS2‐MoO2 during a long cycling process. Meanwhile, the synergistic effect among the MoS2, MoO2, and rGO components are responsible for abundant active sites and shorten ionic transport channels. When evaluating as anode material for LIB, MoS2‐MoO2/rGO sample presents excellent cyclic performance and still delivers a high capacity of 1062.3 mA h g−1 after 120 cycles at 0.2 A g−1; evaluating in a SIB at 0.04 A g−1, it presents excellent cyclic performance and delivers 430 mA h g−1 at the 80th cycle. The heterostructural composite MoS2‐MoO2/rGO is one of the candidate anode materials for high‐performance LIB and SIB. [ABSTRACT FROM AUTHOR]

Introduction: The effect of dipeptidyl peptidase-4 (DDP-4) inhibitors versus α-glucosidase inhibitors (AGIs) on the treatment of type 2 diabetes mellitus (T2DM) in a real-world setting is unknown. The aim of this real-world study was to compare the glucose-lowering effect and tolerability of vildagliptin as add-on to metformin monotherapy (VM) and AGI as add-on to metformin monotherapy (AM) in Chinese patients with T2DM. Methods: This was a subgroup analysis of the China Prospective Diabetes Study, a post-marketing, prospective, observational, real-world study conducted at 52 centers in China. T2DM patients with inadequate glycemic control on metformin monotherapy who received VM or AM were included. The composite primary endpoint was glycemic control (hemoglobin A1c [HbA1c] < 7%) after 12 months in the absence of tolerability events (hypoglycemia, weight gain ≥ 3%, or gastrointestinal events leading to treatment discontinuation). Propensity score matching (PSM) was used to balance the two groups. Results: The success rates of the composite endpoint were higher in the VM group (n = 604/159 before/after PSM) than in the AM group (n = 159/157 before/after PSM), but the difference was not statistically significant (before PSM: 53.0 vs. 46.5%, P = 0.148; after PSM: 56.7 vs. 45.9%, P = 0.055). The glycemic control rate and HbA1c reduction were similar between groups at 3, 6, and 12 months. Compared with the AM group, the VM group had lower risks of any tolerability event (relative risk [RR] 0.53, 95% confidence interval [CI] 0.33–0.83, P = 0.006), of any adverse event (AE) (RR 0.64, 95% CI 0.41–1.00, P = 0.049), and of any serious AE (RR 0.45, 95% CI 0.25–0.81, P = 0.007). Conclusion: The results of this real-world study suggest that vildagliptin as add-on to metformin monotherapy had a similar glucose-lowering effect to AGI as add-on to metformin monotherapy, but with better safety. [ABSTRACT FROM AUTHOR]

Abstract Li 1.147 K 0.026 Mn 0.582 Ni 0.25 O 2 (LKMNO) sample is successfully prepared by doping K+ ions into Li slab without changing the original structure of Li 1.167 Mn 0.575 Ni 0.25 O 2 (LMNO). LKMNO sample delivers the capacities of 160.2 and 135.1 mAh g−1 at 1 and 5 C rates, respectively, but LMNO sample only delivers 135.1 and 0 mAh g−1. After 100 cycles at 1 C rate, LMNO and LKMNO samples respectively remain 67.4% and 93.0% of their initial capacities. The effects of K+ doping on the relationship between the charging-discharging process and phase change are detailed studied by the incremental capacity curves (d Q/ d V) at the various cycles. K+ doping in LKMNO sample plays an essential role in rate performance and cyclic performance, because it effectively hinders the formation of spinel structure and stabilizes the host layered structure. Considering the irreversible extraction of Li and O from the Li 2 MnO 3 region occurred beyond 4.6 V, after the charging/discharging are collected for 1–5 cycles at 2.5–4.9 V and 6–300 cycles at 2.5–4.6 V, LKMNO sample further reveals a remarkable improvement in cycling performance. In the full cell state (pouch cell), the discharge capacity of LKMNO is 194.6 and 115.4 mAh g−1 at 0.1 and 1 C rates, respectively, which are much higher than 175.5 and 79.7 mAh g−1 of LMNO sample. The capacity retention of LMNO and LKMNO samples is respective 48.8% and 74.9% of their initial capacity after 100 cycles. Graphical abstract Image 1 Highlights • Li 1.147 K 0.026 Mn 0.582 Ni 0.25 O 2 is successfully prepared by doping K+ into Li slab. • K+ doping results in Mn3+ state and is essential in rate and cyclic performance. • After 100 cycle LMNO and LKMNO remain 67.4% and 93.0% of their initial capacities. • K+ doping hinders the formation spinel structure and stabilizes the host structure. • In full cell LKMNO delivers two times capacity than LMNO at 1 C rate. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The α-Fe 2 O 3 grains were grafted onto the TiO 2 /CNFs via the vapor-solid reaction. • The TiO 2 /CNFs reserved void space to suppress the disintegration of the Fe 2 O 3. • The 3D network provide interstitial sites and enhanced pathways for Li+ and e−. Abstract α-Fe 2 O 3 grains grafted onto TiO 2 /carbon nanofibers (CNFs) for use as anode materials in lithium-ion batteries have been successfully fabricated by electrospinning and vapor-solid reaction (VSR). Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N 2 adsorption-desorption isotherms reveal that the ultrafine α-Fe 2 O 3 nanoparticles were formed on the TiO 2 /CNFs and have uniform dispersion along the fiber direction. The VSR approach could retard nucleation, thus making TiO 2 /CNFs with small Fe 2 O 3 grains grafting (approximately 5 nm in diameter). The TiO 2 /CNFs are capable of buffering the large volume variation of α-Fe 2 O 3 during cycling and preventing electrode pulverization and aggregation, as well as providing sufficiently large interstitial space within the crystallographic structure to host Li ions. The electrochemical properties of the composite electrodes were tested by galvanostatic cycling at both constant and variable current rates. The composite delivers both good rate capability under an uprated current density of 1000 mA g−1 and especially enhanced cycle stability (∼600 mA h g−1 after 200 cycles at a current density of 1000 mA g−1). The super electrochemical performance is attributed to a synergetic effect between α-Fe 2 O 3 and TiO 2 -CNFs as well as the three- dimensional (3D) network, which contributes to greatly enhanced diffusion kinetics and structural stability for lithium-ion batteries. This VSR approach can be extended to other hierarchical metal oxide nanostructures for favorable applications in electrochemical devices. [ABSTRACT FROM AUTHOR]

Tin-based materials are considered to be next-generation anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacity and safety, but their large volume expansion results in rapid capacity fading. In this work, the heterostructure of Sn|SnO 2 submicron particles supported by carbon fibers and amorphous carbon layers (CF/Sn|SnO 2 @C) is successfully synthesized by hydrothermal and thermal treatments. Sn|SnO 2 submicron particles are uniformly grown on CF and encased in the CF network. Herein, CF together with a layer of amorphous carbon not only buffers the volume change of Sn|SnO 2 to prevent its pulverization and dissolution but also improves the electric and lithium ionic transportation capabilities during the lithiation/delithiation cycle. The CF/Sn|SnO 2 @C film can directly act as a binder-free anode for LIBs, exhibits a stable capacity of 657.6 mAh g −1 at a current density of 0.1 A g −1 after 50 cycles and presents better rate capacities than the Sn|SnO 2 @C comparison sample. Taking advantage of the stabilization and conductive channels of CF, this work demonstrates potential applications in the preparation of CF-based, binder-free anodes for LIBs in which metal oxide submicron particles can be effectively supported by a CF network. [ABSTRACT FROM AUTHOR]

Columbite compound MnNb 2 O 6 , consisted the layers with slightly distorted hexagonal-closed-packed oxygen sublattice, has abundant reaction sites whereby the interlayered ions can occur faradic reaction to enhance the charge storage capability. Here, we first report three-dimensional nanostructure of MnNb 2 O 6 as electrode materials for electrochemical pseudocapacitor synthesized through hydrothermal method. The crystal morphologies of MnNb 2 O 6 show an evolution with the hydrothermal time, from primary spindle-like particles grown for 12 h and undergrown star-like crystals for 18 h, to hierarchical star-like crystals for 1 day and overgrown crystals for 3 days. MNO-1d sample synthesized for 1 day possesses ordered six-leaf nanostructure composed of hierarchical nano-sheets (thickness ∼30 nm). To explore its potential applications for supercapacitor, MnNb 2 O 6 sample as electrode material is characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge–discharge measurements. MNO-1d demonstrates an outstanding specific capacitance of 350 F g −1 and rate capability with a high capacitance retention of ∼90% of its initial capacitance after 10000 cycles at a high current density of 10 A g −1 . [ABSTRACT FROM AUTHOR]

A novel heterostructure of NiO/Ni 3 S 2 nanoflake is synthesized and composited with carbon nanofibers (CNF) membrane. NiO/Ni 3 S 2 nanoflakes are homogeneously dispersed in CNF network, herein, NiO/Ni 3 S 2 like leaf and CNF like branch. Carbon nanofibers network efficiently prevents the pulverization and buffers the volume changes of NiO/Ni 3 S 2 , meanwhile, NiO/Ni 3 S 2 nanoflakes through the conductive channels of carbon nanofibers own improved Li + diffusion ability and structural stability. The capacity of NiO/Ni 3 S 2 /CNF reaches to 519.2 mA g −1 after 200 cycles at the current density of 0.5 A g −1 while NiO/Ni 3 S 2 fades to 71 mAh g −1 after 40 cycles. Owing to the synergetic structure, the resultant binder-free electrode NiO/Ni 3 S 2 /carbon nanofibers shows an excellent reversible lithium storage capability. [ABSTRACT FROM AUTHOR]

Li 1.24 Ni 0.12 Co 0.12 Mn 0.56 O 2 (LNCM) with high specific capacity is a potential cathode for commercial lithium-ion batteries (LIBs). To improve the high-rate capacity and cyclic stability, LNCM sample is successfully coated by minor AlF 3 . The crystal structure and electrochemical properties of the bare and coated samples are investigated by X-ray diffractometry (XRD), scanning and transmission electron microscopy (SEM, TEM), cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT), and charge/discharge measurements. The coating layer AlF 3 efficiently plays a positive role in enhancing rate performance and cyclic stability of LNCM. At 0.5 A g −1 , the specific discharge capacity of LNCM@2%AlF 3 is 149 mAh g −1 much higher than 35 mAh g −1 in bare LNCM. At 20 mA g −1 , the specific discharge capacity of LNCM@2%AlF 3 is 223 mAh g −1 at the 60th cycle in comparison with 203 mAh g −1 in bare LNCM. Moreover, a proper AlF 3 coating layer efficiently ensures the stability of LNCM cathode operated at higher temperature. LNCM@2%AlF 3 operated at 55 °C remains 219 mAh g −1 at the 50th cycle, much higher than bare LNCM only remains 99 mAh g −1 at the 40th cycle. [ABSTRACT FROM AUTHOR]

Amorphous vanadyl phosphate/graphene nanohybrids is successfully synthesized by first exfoliating bulk layered vanadyl phosphate (VOPO 4 ·2H 2 O) into nanosheets, and then hydrothermal treatment with graphene oxide (GO). The electrochemical properties of the resulted materials are systematically investigated. It is found that a phase transformation from crystalline to amorphous is occurred to VOPO 4 ·2H 2 O. As supercapacitor electrode material, the amorphous VOPO 4 /graphene composite exhibits a high specific capacitance (508 F g −1 at 0.5 A g −1 ), an excellent rate capability (359 F g −1 at 10 A g −1 ), and a good cycling stability (retention 80% after 5000 cycles at 2 A g −1 ). Particularly, it simultaneously has a greatly enhanced energy density of 70.6 Wh·kg −1 with a power density of 250 W kg −1 . The outstanding energy storage performance mainly originates from the generation of amorphous VOPO 4 phase that facilitates ion transport by shortening ion diffusion paths and provides more reversible and fast faradic reaction sites, the hybridization with graphene that greatly improves the electric conductivity and structure stability, and the unique layer-on-sheet nanohybrid structure that effectively enhances the structure integrity. This work not only provides a facile method for the preparation of amorphous VOPO 4 /graphene composites, but also demonstrates the enhanced energy density and rate capability of amorphous VOPO 4 -based materials for potential application in supercapacitors. [ABSTRACT FROM AUTHOR]

In recent years, enormous effort have been made in recycling spent lithium-ion batteries (LIBs), but more efficient and energy efficient methods still need to be found. In this work, we propose a new recycling process which can directly use recycled metals as raw materials to re-synthesize LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode material based on co-precipitation method. The influence of temperature on the physical and electrochemical properties of the regenerated material has been studied by changing sintering temperature. The as-produced regenerated cathode materials gain the electrochemical performance as well as the commercial LiNi 0.5 Co 0.2 Mn 0.3 O 2. Cop-830 ℃ obtained at sintering temperature of 830 ℃ still delivers 149.2 mAh g−1 after 100 cycles at 0.2 C rate, which is 92.4% of its initial capacity. It confirms that the optimized sintering temperature is essential for the regeneration of spent ternary cathode materials in potential application. • Recycling process is successfully processed directly use recycled metals. • LiNi 0.5 Co 0.2 Mn 0.3 O 2 was regenerated from spent LIBs by co-precipitation method. • Electrochemical properties of regenerated materials reach to commercial materials. • Cop-830 ℃ delivers 149.2 mAh g−1 after 100 cycles at 0.2 C, 92.4% of initial capacity. [ABSTRACT FROM AUTHOR]

The somatic cell nuclear transfer (SCNT) technique could be used to produce genetically superior or genetically engineered cloned pigs that have wide application in agriculture and bioscience research. However, the efficiency of porcine SCNT currently is very low. Embryo transfer (ET) is a key step for the success of SCNT. In this study, the effects of several ET-related factors, including cloned embryo culture time, recipient's ovulation status, co-transferred helper embryos and ET position, on the success rate of pig cloning were investigated. The results indicated that transfer of cloned embryos cultured for a longer time (22–24 h vs. 4–6 h) into pre-ovulatory sows decreased recipient's pregnancy rate and farrowing rate, and use of pre-ovulatory and post-ovulatory sows as recipients for SCNT embryos cultured for 22–24 h resulted in a similar porcine SCNT efficiency. Use of insemination-produced in vivo fertilized, parthenogenetically activated and in vitro fertilized embryos as helper embryos to establish and/or maintain pregnancy of SCNT embryos recipients could not improve the success rate of porcine SCNT. Transfer of cloned embryos into double oviducts of surrogates significantly increased pregnancy rate as well as farrowing rate of recipients, and the developmental rate of transferred cloned embryos, as compared to unilateral oviduct transfer. This study provided useful information for optimization of the embryo handling and transfer protocol, which will help to improve the ability to generate cloned pigs. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) contain a variety of toxic inorganic and organic compounds, and the spent cathode materials are high quality resources of Ni, Co, Mn, and Li elements. In this case, how to efficiently deal with spent materials has become an urgent problem. In this work, the regeneration of spent ternary materials via molten salt solid-liquid method and traditional solid-solid method are studied comparatively. Ordered and uniform crystals in MS-NCM are successfully grown in liquid medium of molten salts. The regenerated TS-NCM by traditional sintering method still presents inhomogeneous larger and smaller crystals. Moreover, only regeneration by molten salt method effectively removes F-contained impurity on the surface of spent materials, and the Ni3+ and Mn3+ on the crystal surface of MS-NCM are close to the values in commercial sample (Com-NCM). After 100 cycles at 0.2 C rate, MS-NCM and TS-NCM respectively deliver 149.1 mA h g−1 and 123.2 mA h g−1, maintaining 98.1% and 84.4% of their initial capacity. MS-NCM presenting better electrochemical performance than TS-NCM is attributed to the efficient regeneration of the spent cathode material in liquid medium of molten salts. [Display omitted] • Spent NCM regeneration via solid-liquid better than traditional via solid-solid. • Uniform NCM crystals successfully re-grown in liquid medium of molten salts. • Regeneration in molten salts effectively supplement Li+ and remove F-impurity. • MS-NCM delivers much higher capacity than TS-NCM after 100 cycle. [ABSTRACT FROM AUTHOR]

• Micron single crystals of LiNi 0.8 Co 0.1 Mn 0.1 O 2 were prepared by molten salt method. • SC-NCM has lower cationic mixing accompanying with ordered growth of micron crystal. • Ni(III) in SC-NCM is majority benefiting for cyclic stability. • After 300 cycles at 5C rate SC-NCM remains 80.7 mAh g−1 and retention 62.0%. • Micron single crystals on electrochemical property benefit for structure stability. In this work, Ni-rich layered micron-sized LiNi 0.8 Co 0.1 Mn 0.1 O 2 (SC-NCM) single crystals were prepared by wet ball-milling and molten-salt methods. Through X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectrometry (XPS), the differences between SC-NCM and a commercial polycrystalline micron-sized NCM material (M-NCM) were compared. An extended sintering process for SC-NCM plays a role in decreasing cationic mixing accompanied by the ordered growth of single crystals. The SC-NCM sample presents homogeneous micron-sized crystals. The Ni3+ content in SC-NCM constitutes 90.45% of the total Ni content, while the Ni3+ in M-NCM constitutes only 68.49%. The existence of Ni2+ in ternary cathode materials is harmful to electrochemical stability and cyclic stability. The initial specific discharge capacity of SC-NCM (168 mAh g−1) is lower than that of M-NCM (187 mAh g−1); however, M-NCM shows a rapid decline in capacities and voltage plateaus from the 1st to 180th cycle. After 300 cycles at a 5 C rate, M-NCM remains only 42 mAh g−1 with a capacity retention rate of only 25.6% in comparison with SC-NCM with a remaining capacity of 80.7 mAh g−1 and a capacity retention of 62.0%. The effect of micron-sized single crystals on electrochemical properties during redox reactions is negative in terms of conductivity but positive in terms of structural stability. [ABSTRACT FROM AUTHOR]

Abstract: In this work, high specific capacitance of Mn3O4 is successfully synthesized via ultrasonic and hydrolyzation at room temperature. The crystal structure, phase and the electrochemical performance are dependent on the preparation conditions, such as ultrasonic time, reaction temperature, and the organic solvent used, etc. The effect of ultrasonic time and the presence of various solvents are well discussed in the crystal growth mechanism and improved supercapacitor performance of Mn3O4. The almost 100% yielded Mn3O4 nanoparticles via ultrasonication for 6h at room temperature exhibit high specific capacitances (261Fg−1 at 0.4Ag−1 and 140Fg−1 at 40Ag−1) as well as excellent cycle life. The high yield and convenient synthetic route at room temperature make readily scaled-up production of transition metal oxides for electrochemical applications. [Copyright &y& Elsevier]

Abstract: To substitute minor Mn2+ by the transition metal ion M=Mg2+, V3+, Fe2+, Co2+, or Gd3+, LiMn0.95M0.05PO4 samples are synthesized by a solid-state reaction route. The interpretation of doping effects is complicated by the interrelations between doping microstructure and morphology, because the crystal structure would be affected by the doped elements. The lattice structure and deviation of Li–O bond lengths of the doped LiMnPO4 are refined by XRD refinement. All the samples present a couple of oxidation and reduction peaks in cyclic voltammetry, corresponding to a redox Mn3+/Mn2+ reaction coupled with the extraction/reinsertion process of Li+ in LiMnPO4 structure. During charge/discharge process, the electron flowing and Li+ cation diffusion in the various doped LiMnPO4 samples should be different thermodynamic and kinetic process. For further studying which step in thermodynamic and kinetic process would affect or control the electrochemical performance, the initial charge/discharge capacities and cycleability of doped LiMnPO4 samples are obtained under different voltage range (from 2.7 to the upper cut-off voltage 4.4, 4.6 and 4.8V, respectively) and different environment temperatures (0, 25, and 50°C). At relative higher measuring temperature, the discharge capacity of Co-doped LiMnPO4 shows 151.9mAhg−1. [Copyright &y& Elsevier]

Abstract: Two enantiomerically pure chiral POM-based compounds, [(CH3)2NH2]10[Zr(PW11O39)2]·10H2O (Left-1, L-1 for short and Right-1, R-1 for short) have been prepared by conventional aqueous solution method without a chiral auxiliary and structurally characterized by single-crystal X-ray diffraction. The structures of L-1 and R-1 contain two lacunary [PW11O39]7− units, each acting as a tetra-dentate ligand, the ZrIV cation sandwiched between two [PW11O39]7− anions is of eight coordination and occupies a distorted square antiprismatic geometry. The circular dichroism spectra confirmed the occurrence of spontaneous resolution and the enantiomeric nature of L-1 and R-1. Cyclic voltammetric experiment for 1 represents two redox peaks corresponding to the redox processes of [PW11O39]7− in the potential range from −1000 to 1000mV. [Copyright &y& Elsevier]

Abstract: Two novel compounds constructed by Anderson-type polyoxoanions and copper complexes with mixed ligands, (H3O+)[Cu(C6NO2H4)(phen)(H2O)]2[Al(OH)6Mo6O18]·5H2O (1) and (H3O+)[Cu (C6NO2H4)(phen)(H2O)]2[Cr(OH)6Mo6O18]·5H2O (2) have been isolated by conventional solution method, and characterized by elemental analyses, IR spectra, thermal stability analyses, X-ray powder diffraction and single-crystal X-ray diffraction. Compounds 1 and 2 are isomorphic and reveal an example of three-dimensional supramolecular organic–inorganic hybrids based on copper complexes with mixed 1,10-phenanthroline and pyridine-4-carboxylic acid ligands supported on Anderson-type polyoxoanions. Furthermore, both of the compounds exhibit photoluminescent properties at ambient temperature, and to elucidate the electronic properties of the metal ions (Cu2+ or Cu2+/Cr3+), EPR studies have been performed, and the results are in good agreement with the structural feature of these compounds. [Copyright &y& Elsevier]

[Display omitted] • Super-hydrophilic microporous biochar prepared by a simple and safe method from biowastes. • Detailed interpretation on the surface characteristics for exploring the charge storage mechanism. • High and durable charging/discharging capacitance as supercapacitor electrode. Super-hydrophilic microporous biochar materials, for supercapacitor application, are prepared through a simple and safe method from pomelo peel. Zinc nitrate and urea are used as activator, porogen and nitrogen source, which generate gases moderately and avoid the risk of explosion in calcination. This method endows the biochar products with abundant micropores and extraordinary large N and O doping content (>20% in atomic ratio). Such large doping content leads to super-hydrophilicity, which in turn makes the micropores available for charge storage. In addition, under a moderate calcination condition (700 ℃, 2 h), the biochar material gains large conductivity, without diminishing the super-hydrophilicity. Theoretical analysis on characterizations demonstrates that, the higher ratio of sp2 C and larger proportion of quaternary N (N-Q) in this material (CNO700) account for its much higher conductivity. The synergetic effect of large pore volume (0.69 cm3·g−1), high N and O doping content, proper ratio of N species and large conductivity (0.713 S·m−1) makes the material (CNO700) exhibit high and durable specific capacitance, i.e., 391.0 F·g−1 at 0.5 A·g−1, and cycling stably for >25,000 times at 10.0 A·g−1 with good capacitance retention. [ABSTRACT FROM AUTHOR]

Abstract: Triangular and hexagonal CdS nanoplates, with average size about 100 nm and average thickness range from 10 to 30 nm, have been synthesized in the presence of poly (acrylic acid) (PAA) assisted hydrothermal process at 180 °C. The structural characteristics, morphology, and optical properties of the as-prepared CdS products were investigated. UV–vis spectroscopy measurement reveals that the products show a strong quantum size effect. Based on the experiment results, the possible formation mechanism of CdS nanoplates has been proposed. [Copyright &y& Elsevier]

Abstract: High quality Mn-doped CdS nanowires have been synthesized through solvothermal route with Polyethylene Glycol-400 as inducing template at 170°C. The nanowires had a uniform single-crystal hexagonal structure and preferentially grew along [001] direction. Undoped and doped CdS nanowires with 1% Mn have been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy dispersive X-ray analysis (EDX). Also, investigations into the optical properties of the Mn2+ doped CdS nanowires were conducted with UV–vis absorption spectroscopy and photoluminescence emission spectroscopy. The luminescence due to Mn2+ intra-3d transition is clearly observed near 595nm in Mn-doped CdS nanowires. [Copyright &y& Elsevier]

Lithium-rich cathode materials have the potential for applications in high energy lithium-ion batteries, but they suffer from a low rate performance and an inferior cycling stability. In this work, Li 1.167- x K x Mn 0.583 Ni 0·25 O 2 (x = 0, 0.025, 0.05 and 0.075) samples are synthesized and characterized. In addition, K+ doping results in small perturbations in the crystal structure of Li 1.167- x K x Mn 0.583 Ni 0·25 O 2 , such as the Li–O bond lengths, lattice parameters and the oxidation states of manganese, which effectively improves the lithium diffusion ability and hinders the detrimental interphase growth of the spinel phase during cycling. In a half-cell, Li 1·117 K 0·05 Mn 0·583 Ni 0·25 O 2 (LK2MNO) with an optimized doping quantity of K+ delivers the best capacities of 152.0 mAh g−1 after 100 cycles at a 1C rate and 82.9 mAh g−1 after 300 cycles at a 10C rate, in comparison with Li 1·167 Mn 0·583 Ni 0·25 O 2 , which has a capacity of only 126.0 and 33.3 mAh g−1. In the full-cell with graphite as the negative electrode, LK2MNO delivers an initial capacity of 249.9 mAh g−1 at a 0.1C rate and retains 90.8% of its initial capacity after 100 cycles. The surface chemical states of the positive electrode and negative electrodes after 100 cycles is studied by ex situ SEM and XPS measurements, and the results reveal that an appropriate K+ doping amount effectively hinders the dissolution of Mn2+ from the cathode material and decreases the decomposition of electrolytes to some degree. K+ doping in Mn-based lithium-rich cathode materials improves the lithium diffusion ability and hinders the detrimental interphase growth of the spinel phase during cycling. In full cell, the LK2MNO sample delivers an initial capacity of 249.9 mAh g−1 at a 0.1C rate and retains 90.8% of its initial capacity after 100 cycles. The surface chemical state of the positive and negative electrodes after 100 cycles reveal that K+ doping effectively suppresses side reactions and electrolyte decomposition. Image 1 • K+ doping results in small perturbations in Li 1.167- x K x Mn 0.583 Ni 0·25 O 2 structure. • Potassium doping decreases the detrimental interphase growth of spinel phase during cycling. • Expanding interlayer spacing by K+ provide fast conductive channel for Li+ diffusion. • LK2MNO delivers 249.9 mAh g−1 and remains 90.8% of initial capacity after 100 cycles. • K+ doping suppresses side reactions and electrolyte decomposition during cycling. [ABSTRACT FROM AUTHOR]