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Lithium (Li) metal is promising for high energy density batteries due to its low electrochemical potential (-3.04 V) and high specific capacity (3860 mAh g -1 ). However, the safety issues impede the commercialization of Li anode batteries. In this work, research of hierarchical structure designs for Li anodes to suppress Li dendrite growth and alleviate volume expansion from the interior (by the 3D current collector and host matrix) to the exterior (by the artificial solid electrolyte interphase (SEI), protective layer, separator, and solid state electrolyte) is concluded. The basic principles for achieving Li dendrite and volume expansion free Li anode are summarized. Following these principles, 3D porous current collector and host matrix are designed to suppress the Li dendrite growth from the interior. Second, artificial SEI, the protective layer, and separator as well as solid-state electrolyte are constructed to regulate the distribution of current and control the Li nucleation and deposition homogeneously for suppressing the Li dendrite growth from exterior of Li anode. Ultimately, this work puts forward that it is significant to combine the Li dendrite suppression strategies from the interior to exterior by 3D hierarchical structure designs and Li metal modification to achieve excellent cycling and safety performance of Li metal batteries., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Recently, crystal-phase engineering has been emerging as a promising strategy to tune the physicochemical properties of noble metal catalysts and further improve their catalytic performance. However, the synthesis of noble metal catalysts with an unconventional crystal phase as well as desired composition and morphology still remains a great challenge. Herein, a series of PdM (M = Zn, Cd, ZnCd) nanosheets (NSs) with thickness less than 5 nm have been synthesized via a facile one-pot wet-chemical method. In particular, different from the conventional face-centered cubic ( fcc ) phase, PdM NSs possess an unconventional face-centered tetragonal ( fct ) phase. As a proof-of-concept application, the fct PdZn NSs exhibit significantly enhanced mass activity and stability in ethanol oxidation reaction, compared to the pure Pd NSs and commercial Pd black catalyst.

Li 4 Ti 5 O 12 (LTO) as the anode of lithium (Li) ion batteries has high interfacial side reactivity with the electrolyte, which leads to severe gassing behavior and poor cycling stability. Herein, the capacity loss mechanism of the high-tap density LTO microsphere anode under different temperatures (25, 45, and 60 °C) and charge/discharge rates (1 and 5 C) is systematically investigated. The capacity retentions of the LTO/Li cell after 500 cycles at 1 C are 95.6, 90.0, and 87.1% under three temperatures, which drop to 91.9, 58.3, and 20.9% when cycling at 5 C, respectively. Results show that the high temperature and rate almost do not damage the structure of LTO, but greatly affect the thickness and components of the solid electrolyte interface (SEI), and consequently reduce the performance of the LTO/Li cells. An SEI mainly consisting of inorganic species forms on LTO after 500 cycles at 1 C, while organic compounds are observed after 500 cycles at 5 C. The capacity of cycled LTO cannot recover again because of the thick SEI although using new Li metal anodes, separators, and electrolytes. This work demonstrates that it is of great significance for LTO to construct a stable SEI for achieving excellent cycling performance at a high rate and temperature.

Designing composite structures of active materials is critical for high-performance lithium-ion batteries, as it determines the reversibility of lithium-ion insertion and extraction of the electrodes. The V 2 O 3 anode has a high specific capacity but presents poor cycling stability due to a large volume change. Herein, a novel C@V 2 O 3 -Li 4 Ti 5 O 12 composite with ultrastable cycling stability is constructed. In this composite structure, the interconnected ultrasmall V 2 O 3 and Li 4 Ti 5 O 12 nanoparticles (5-10 nm) construct robust interfaces in the carbon matrix. The Li 4 Ti 5 O 12 nanoparticles with excellent cycling stability and a minor volume change act as fixtures that effectively restrict the volume change of V 2 O 3 nanoparticles and improve the cycling stability of the C@V 2 O 3 -Li 4 Ti 5 O 12 composite. The C@V 2 O 3 -Li 4 Ti 5 O 12 composite maintains no degradation during 500 cycles under a current density of 100 mA g -1 . The results demonstrate that constructing a highly stable interface between the active nanoparticles with smaller and larger volume changes is of great significance to suppress their pulverization and achieve high reversibility. This work contributes to a new strategy to design the structure of long-cycling anode materials for highly stable lithium-ion batteries.

Pd-encapsulated porous carbon materials (Pd-PCMs) were prepared from the coupling polymerization of an aryl halide and aryl alkyne under mild conditions. Combining its porous microstructure and encapsulated Pd nanoparticles, Pd-PCMs with high sulfur loading reach a capacity of 920 mA h g-1 after 200 cycles at 0.3C.

Solid electrolytes are considered as strong alternatives for conventional liquid electrolytes to overcome the safety issues of next-generation high-energy-density lithium metal batteries (LMBs). Although Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) has satisfied ionic conductivity at room temperature (∼10 -4 S cm -1 ), high stability in air, and can be easily sintered, it still suffers from instability of the lithium metal. Moreover, the large interfacial resistance between solid electrolytes and solid electrodes and the stress generated by the volumetric change of lithium metal anodes during cycling would deteriorate the performance of LMBs. Here, we report an effective solution to overcome the abovementioned problems by introducing a three-dimensional gel polymer electrolyte at the interface between LAGP pellets and lithium metal anodes, achieving stable cycling of LiFePO 4 //Li cells at room temperature for 300 cycles. Besides, the degeneration mechanisms of the interfaces of LAGP pellets under different conditions are compared, and peculiar properties different from their counterparts were found.

Cadmium (Cd) pollution in rice and its transfer to food chain are cause of global concern. Application of zinc (Zn) can reduce Cd uptake by plants, as both these metals are generally antagonistic in soil-plant systems. In a field experiment on Cd-contaminated acid soil, we investigated the effectiveness of foliar application of Zn in minimizing Cd accumulation and its effect on the content of mineral nutrient elements in rice. The treatment was done at an early grain filling stag using 0.3 and 0.5% w/v ZnSO 4 ·7H 2 O solution. The spray did not affect the grain yield of rice but decreased the Cd concentration in the root, straw, husk, and brown rice to some extent and increased the Zn concentration. Foliar application of 0.5% ZnSO 4 resulted in maximum Zn concentration and minimum Cd concentration in brown rice. However, the concentrations of P, K, Ca, Mg, Cu, and Mn in brown rice were not affected. The correlation between Cd and Zn concentrations in brown rice, husk, and root was significantly negative, and that between Cd and Mn concentrations in brown rice was significantly positive. The inhibition of Cd uptake resulted in a decrease in its concentration in brown rice after the treatments. Thus, the foliar application of a suitable concentration of Zn at the early grain filling stage could effectively minimize the Cd concentration while enhancing the Zn concentration in brown rice on Cd-contaminated acid soil.

The practical application of tin dioxide (SnO2) in lithium-ion batteries has been greatly hindered by its large volumetric expansion and low conductivity. Thus, a rational design of the size, geometry and the pore structure of SnO2-based nanomaterials is still a dire demand. To this end, herein we report an effective approach for engineering hollow-structured SnO2 nanospheres with adequate surface oxygen vacancies simultaneously wrapped by a nitrogen-doped graphene network (SnO2-x/N-rGO) through an electrostatic adsorption-induced self-assembly together with a thermal reduction process. The close electrostatic attraction achieved a tight and uniform combination of positively charged SnO2 nanospheres with negatively charged graphene oxide (GO), which can alleviate the aggregation and volume expansion of the entrapped SnO2 nanospheres. Subsequent thermal treatment not only ensures a significant reduction of the GO sheets accompanying nitrogen-doping, but also induces the generation of oxygen vacancies on the surface of the SnO2 hollow nanospheres, together building up a long-range and bicontinuous transfer channel for rapid electron and ion transport. Because of these structural merits, the as-built SnO2-x/N-rGO composite used as the anode material exhibits excellent robust cycling stability (∼912 mA h g-1 after 500 cycles at 0.5 A g-1 and 652 mA h g-1 after 200 cycles at 1 A g-1) and superior rate capability (309 mA h g-1 at 10 A g-1). This facile fabrication strategy may pave the way for the construction of high performance SnO2-based anode materials for potential application in advanced lithium-ion batteries.

Porous current collectors are conducive to enhance the property of Li metal anode. Unfortunately, congestion in diffusion path during plating process damages the effects of current collectors. Herein, we developed a 3D Cu skeleton with open micrometer-sized pores by NaCl-assisted powder-sintering method. The unobstructed pores of 3D Cu skeleton help to reduce congestion during plating, thus most of Li deposited inside the current collector. Besides, the large smooth surface promotes the deposition of Li with smooth spherical shape, which mitigating Li dendrite growth. As a result, better safety and rechargeability of Li metal anode were achieved in this design.

Lithium-sulfur (Li-S) batteries are considered as one of the most promising energy storage systems for next-generation electric vehicles because of their high-energy density. However, the poor cyclic stability, especially at a high sulfur loading, is the major obstacles retarding their practical use. Inspired by the nacre structure of an abalone, a similar configuration consisting of layered carbon nanotube (CNT) matrix and compactly embedded sulfur is designed as the cathode for Li-S batteries, which are realized by a well-designed unidirectional freeze-drying approach. The compact and lamellar configuration with closely contacted neighboring CNT layers and the strong interaction between the highly conductive network and polysulfides have realized a high sulfur loading with significantly restrained polysulfide shuttling, resulting in a superior cyclic stability and an excellent rate performance for the produced Li-S batteries. Typically, with a sulfur loading of 5 mg cm -2 , the assembled batteries demonstrate discharge capacities of 1236 mAh g -1 at 0.1 C, 498 mAh g -1 at 2 C and moreover, when the sulfur loading is further increased to 10 mg cm -2 coupling with a carbon-coated separator, a superhigh areal capacity of 11.0 mAh cm -2 is achieved.

In this work, high-level heteroatom doped two-dimensional hierarchical carbon architectures (H-2D-HCA) are developed for highly efficient Li-ion storage applications. The achieved H-2D-HCA possesses a hierarchical 2D morphology consisting of tiny carbon nanosheets vertically grown on carbon nanoplates and containing a hierarchical porosity with multiscale pore size. More importantly, the H-2D-HCA shows abundant heteroatom functionality, with sulfur (S) doping of 0.9% and nitrogen (N) doping of as high as 15.5%, in which the electrochemically active N accounts for 84% of total N heteroatoms. In addition, the H-2D-HCA also has an expanded interlayer distance of 0.368 nm. When used as lithium-ion battery anodes, it shows excellent Li-ion storage performance. Even at a high current density of 5 A g -1 , it still delivers a high discharge capacity of 329 mA h g -1 after 1,000 cycles. First principle calculations verifies that such unique microstructure characteristics and high-level heteroatom doping nature can enhance Li adsorption stability, electronic conductivity and Li diffusion mobility of carbon nanomaterials. Therefore, the H-2D-HCA could be promising candidates for next-generation LIB anodes.

Vanadium pentoxide (V 2 O 5 ) is considered a promising cathode material for advanced lithium-ion batteries owing to its high specific capacity and low cost. However, the application of V 2 O 5 -based electrodes has been hindered because of their inferior conductivity, cycling stability, and power performance. Herein, hierarchical sisal-like V 2 O 5 microstructures consisting of primary one-dimensional (1D) nanobelts with [001] facets orientation growth and rich oxygen vacancies are synthesized through a facile hydrothermal process using polyoxyethylene-20-cetyl-ether as the surface control agent, followed by calcination. The primary 1D nanobelt shortens the transfer path of electrons and ions, and the stable {001} facets could reduce the side reaction at the interface of electrode/electrolyte, simultaneously. Moreover, the formation of low valence state vanadium would generate the oxygen vacancies to facilitate lithium-ion diffusion. As a result, the sisal-like V 2 O 5 manifests excellent electrochemical performances, including high specific capacity (297 mA h g -1 at a current of 0.1 C) and robust cycling performance (capacity fading 0.06% per cycle). This work develops a controllable method to craft the hierarchical sisal-like V 2 O 5 microstructures with excellent high rate and long-term cyclic stability.

Through a facile sodium sulfide (Na 2 S)-assisted hydrothermal treatment, clean and nondefective surfaces are constructed on micrometer-sized Li 4 Ti 5 O 12 particles. The remarkable improvement of surface quality shows a higher first cycle Coulombic efficiency (≈95%), a significantly enhanced cycling performance, and a better rate capability in electrochemical measurements. A combined study of Raman spectroscopy and inductive coupled plasma emission spectroscopy reveals that the evolution of Li 4 Ti 5 O 12 surface in a water-based hydrothermal environment is a hydrolysis-recrystallization process, which can introduce a new phase of anatase-TiO 2 . While, with a small amount of Na 2 S (0.004 mol L -1 at least), the spinel-Li 4 Ti 5 O 12 phase is maintained without a second phase. During this process, the alkaline environment created by Na 2 S and the surface adsorption of the sulfur-containing group (HS - or S 2- ) can suppress the recrystallization of anatase-TiO 2 and renew the particle surfaces. This finding gives a better understanding of the surface-property relationship on Li 4 Ti 5 O 12 and guidance on preparation and modification of electrode material other than coating or doping.

A 3D network gel polymer electrolyte (3D-GPE) is designed for lithium metal batteries and prepared by an initiator-free one-pot ring-opening polymerization technique. This 3D-GPE exhibits an unprecedented combination of mechanical strength, ionic conductivity, and more importantly, effective suppression of Li dendrite growth. The produced lithium-based battery presents long life, high rate, and excellent safety., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

V 2 O 5 decorated carbon nanofibers (CNFs) are prepared and used as a multifunctional interlayer for a lithium-sulfur (Li-S) battery. V 2 O 5 anchored on CNFs can not only suppress the shuttle effect of polysulfide by the strong adsorption and redox reaction, but also work as a high-potential dam to restrain the self-discharge behavior in the battery. As a result, Li-S batteries with a high capacity and long cycling life can be stored and rested for a long time without obvious capacity fading., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Well-controlled nanostructures and a high fraction of Sn/Li 2 O interface are critical to enhance the coulombic efficiency and cyclic performance of SnO 2 -based electrodes for lithium-ion batteries (LIBs). Polydopamine (PDA)-coated SnO 2 nanocrystals, composed of hundreds of PDA-coated "corn-like" SnO 2 nanoparticles (diameter ca. 5 nm) decorated along a "cob", addressed the irreversibility issue of SnO 2 -based electrodes. The PDA-coated SnO 2 were crafted by capitalizing on rationally designed bottlebrush-like hydroxypropyl cellulose-graft-poly (acrylic acid) (HPC-g-PAA) as a template and was coated with PDA to construct a passivating solid-electrolyte interphase (SEI) layer. In combination, the corn-like nanostructure and the protective PDA coating contributed to a PDA-coated SnO 2 electrode with excellent rate capability, superior long-term stability over 300 cycles, and high Sn→SnO 2 reversibility., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nanosized Li 4 Ti 5 O 12 (LTO) materials enabling high rate performance suffer from a large specific surface area and low tap density lowering the cycle life and practical energy density. Microsized LTO materials have high density which generally compromises their rate capability. Aiming at combining the favorable nano and micro size properties, a facile method to synthesize LTO microbars with micropores created by ammonium bicarbonate (NH 4 HCO 3 ) as a template is presented. The compact LTO microbars are in situ grown by spinel LTO nanocrystals. The as-prepared LTO microbars have a very small specific surface area (6.11 m 2 g -1 ) combined with a high ionic conductivity (5.53 × 10 -12 cm -2 s -1 ) and large tap densities (1.20 g cm -3 ), responsible for their exceptionally stable long-term cyclic performance and superior rate properties. The specific capacity reaches 141.0 and 129.3 mAh g -1 at the current rate of 10 and 30 C, respectively. The capacity retention is as high as 94.0% and 83.3% after 500 and 1000 cycles at 10 C. This work demonstrates that, in situ creating micropores in microsized LTO using NH 4 HCO 3 not only facilitates a high LTO tap density, to enhance the volumetric energy density, but also provides abundant Li-ion transportation channels enabling high rate performance.

Anovel lithiated Si-S battery exploiting an optimized solid-like electrolyte is presented. This electrolyte is fabricated by integrating ether-based liquid electrolyte with SiO 2 hollow nanosphere layer to suppress the shuttle effect and fluoroethylene carbonate additive to optimize the anodic solid electrolyte interface. The prepared lithiated Si-S batteries exhibit enhanced cycle life, low flammability, and strong recovery ability against short-circuit., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two-dimensional nanocarbons are intriguing functional materials for energy storage. However, the serious aggregation problems hinder their wider applications. To address this issue, we developed a unique two-dimensional hierarchical carbon architecture (2D-HCA) with ultrasmall graphene-like carbon nanosheets uniformly grown on hexagonal carbon nanoplates. The obtained 2D-HCA shows an interconnected porous structure and abundant heteroelement doping. When employed as anode for lithium ion batteries, it exhibits a high discharge capacity of 748 m Ah g -1 even after 400 cycles at 2 A g -1 .

Although lithium-sulfur (Li-S) batteries deliver high specific energy densities, lots of intrinsic and fatal obstacles still restrict their practical application. Electrospun carbon nanofibers (CNFs) decorated with ultrafine TiO2 nanoparticles (CNF-T) were prepared and used as a multifunctional interlayer to suppress the volume expansion and shuttle effect of Li-S battery. With this strategy, the CNF network with abundant space and superior conductivity can accommodate and recycle the dissolved polysulfides for the bare sulfur cathode. Meanwhile, the ultrafine TiO2 nanoparticles on CNFs work as anchoring points to capture the polysulfides with the strong interaction, making the battery perform with remarkable and stable electrochemical properties. As a result, the Li-S battery with the CNF-T interlayer delivers an initial reversible capacity of 935 mA h g(-1) at 1 C with a capacity retention of 74.2% after 500 cycles. It is believed that this simple, low-cost and scalable method will definitely bring a novel perspective on the practical utilization of Li-S batteries.

A 3D porous Cu current collector is fabricated through chemical dealloying from a commerial Cu-Zn alloy tape. The interlinked porous framework naturally integrated can accommodate Li deposition, suppressing dendrite growth and alleviating the huge volume change during cycling. The Li metal anode combined with such a porous Cu collector demonstrates excellent performance and commerial potentials in Li-based secondary batteries., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The ability to enhance the specific capacity of Li4Ti5O12 (LTO) is of practical significance and offers the opportunity to increase the energy density of a full LTO-based battery. Widening the discharge cutoff voltage to 0 V is an effective way to increase the capacity of LTO at low current density. However, whether the specific capacity of LTO at large current rates can be enhanced remains largely unknown. Herein, intriguingly, we found that, when cycled down to 0 V (i.e., from 1.0-2.5 to 0-25 V), LTO exhibited greatly enhanced specific capacity at low rates (<5 C), while it showed a rapid capacity fading and a greatly increased charge/discharge potential gap at high rates (>10 C). The decreased lithium-ion diffusion caused by extra lithium-ion intercalation together with increased internal impedance significantly enhances the polarization and reduces the electrochemical reaction kinetics, which, in turn, hinders the lithiation reaction from LTO to Li7Ti5O12 and further to Li9Ti5O12.

The effects of number of graphene layers (n) and size of multilayer graphene sheets on thermal conductivities (TCs) of their epoxy composites are investigated. Molecular dynamics simulations show that the in-plane TCs of graphene sheets and the TCs across the graphene/epoxy interface simultaneously increase with increasing n. However, such higher TCs of multilayer graphene sheets will not translate into higher TCs of bulk composites unless they have large lateral sizes to maintain their aspect ratios comparable to the monolayer counterparts. The benefits of using large, multilayer graphene sheets are confirmed by experiments, showing that the composites made from graphite nanoplatelets (n > 10) with over 30 μm in diameter deliver a TC of ∼1.5 W m(-1) K(-1) at only 2.8 vol %, consistently higher than those containing monolayer or few-layer graphene at the same graphene loading. Our findings offer a guideline to use cost-effective multilayer graphene as conductive fillers for various thermal management applications.

Unlabelled: To investigate the effects of Ulinastatin (UTI) in cerebral ischemia-reperfusion (IR) injury in rats and whether this effect might be related to Aquaporin 4 (AQP4), one hundred and eighty adult male Sprague Dawley (SD) rats, weighing 230-280 g, were randomly divided into 3 groups: sham (S) group, IR group and UTI (U) group. Every group was further divided into 3 sub-groups: 6 h group, 24 h group and 48 h group. The transient focal IR injury was induced by inserting a silicone-coater monofilament nylon suture (0.28 mm) from the right external carotid artery to the origin of the left middle cerebral artery. The suture was removed after 2 h to allow reperfusion. UTI treatment group was injected with UTI 100000 u/kg at the beginning of the reperfusion period, while S group and IR group were injected with the same volume of saline. Samples were taken according to the reperfusion time (6 h, 12 h and 24 h). Infract volume was measured by triphenyl tetrazolium chloride staining, and brain water content was determined by wet-dry weight method and neurological scores were checked with a five-point scale. Expression levels of AQP4 were checked with immunohistochemistry and Western blot., Results: Compared with S group, the infarct volume, water content, neurological scores and AQP4 levels in the rat brain tissues were significantly increased in IR group. Administration of UTI significantly decreased the infarct volume, water content of the brain tissue and neurological scores. Moreover, the expression levels of AQP4 were also down-regulated by UTI treatment., Conclusion: UTI improves cerebral IR injury in rats potentially via decreasing the expression levels of AQP4.