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All-solid-state lithium batteries (ASSLB) are promising candidates for next-generation energy storage devices. Nevertheless, the large-scale commercial application of high energy density ASSLB with the polymer electrolyte still faces challenges. In this study, a thin solid polymer composite electrolyte (SPCE) is prepared through a facile and cost-effective strategy with an infiltration of thermoplastic polyurethane (TPU), lithium salt (LiTFSI or LiFSI), and halloysite nanotubes (HNTs) in a porous framework of polyethylene separator (PE) (TPU–HNTs–LiTFSI–PE or TPU–HNTs–LiFSI–PE). The composition, electrochemical performance, and especially the effect of anions (TFSI− and FSI−) on cycling performance are investigated. The results reveal that the flexible TPU–HNTs–LiTFSI–PE and TPU–HNTs–LiFSI–PE with a thickness of 34 μm exhibit wide electrochemical windows of 4.9 and 5.1 V (vs. Li+/Li) at 60 ℃, respectively. Reduction in FSI− tends to form more LiF and sulfur compounds at the interface between TPU–HNTs–LiFSI–PE and Li metal anode, thus enhancing the interfacial stability. As a result, cell composed of TPU–HNTs–LiFSI–PE exhibits a smaller increase in interfacial resistance of solid electrolyte interphase (SEI) with a distinct decrease in charge-transfer resistance during cycling. Li|Li symmetric cell with TPU–HNTs–LiFSI–PE could keep its stable overpotential profile for nearly 1300 h with a low hysteresis of approximately 39 mV at a current density of 0.1 mA cm−2, while a sudden voltage rise with internal cell impedance-surge signals was observed within 600 h for cell composed of TPU–HNTs–LiTFSI–PE. The initial capacities of NCM|TPU–HNTs–LiTFSI–PE|Li and NCM|TPU–HNTs–LiFSI–PE|Li cells were 149 and 114 mAh g−1, with capacity retention rates of 83.52% and 89.99% after 300 cycles at 0.5 C, respectively. This study provides a valuable guideline for designing flexible SPCE, which shows great application prospect in the practice of ASSLB.

The construction of a lithiophilic phase on the surface of a current collector with a lithiophobic nature is an effective method to suppress Li dendrite growth by reducing the overpotential for Li nucleation and inducing the growth of homogeneous Li nuclei to obtain high-performance lithium metal anodes (LMAs). Nevertheless, the structural regulation of the lithiophilic phase and the underlying mechanism of lithiophilicity have been overlooked in previous studies. In this study, we designed a triporous, nanoporous AuLi3 (NPAuLi3) nanosheet-modified Ni foam (NF) (NPAuLi3@NF) composite current collector for use in LMAs. First principle calculations revealed that the lithiophilicity of the AuLi3 phase originates from the strong electronic interaction between the Au and Li atoms. The morphological characterization demonstrated that the as-designed NPAuLi3@NF current collector not only guided homogeneous Li nucleation and growth during the Li plating process, but also induced uniform Li removal during the Li stripping process, which effectively suppressed Li dendrite growth and formation of dead Li, leading to a boosted electrochemical performance in LMAs. The symmetric Li|Li cells with the NPAuLi3@NF-based LMAs could run stably for 1990 and 1420 h without cell failure at current densities of 1 and 2 mA cm−2 with a capacity of 2 mA h cm−2, respectively, and the Li@NPAuLi3@NF|LFP full cells showed an excellent capacity retention of 83.8% with a coulombic efficiency of 99.8% at 5C after 1000 cycles, and a good rate capability. This work provides insight into the design of the composition and structure of the lithiophilic phase on the surface of the current collector skeleton to obtain high-performance LMAs.

The short life span of lithium metal anodes (LMAs) due to dendrite growth and low coulombic efficiency (CE) has been regarded as the bottleneck in developing next-generation high-energy-density lithium metal based secondary batteries. Employing three-dimensional (3D) current collectors is one approach to reduce the effective current density and delay dendrite growth. Commercial Ni foam, in spite of its high electronic conductivity and 3D topology, has not been considered for this application due to its low specific surface area and lithiophobic nature. In this study, we develop a surface engineering strategy to uniformly coat lithiophilic AuLi3 particles on Ni foam skeletons through lithiation of electrodeposited gold nanoparticles. In comparison with the bare Ni foam, the AuLi3@Ni foam is more lithiophilic, significantly lowering the nucleation energy barrier and enhancing the uniformity for Li deposition. Such a structure results in effective suppression of Li dendrite growth in the void space of the foam. As a result, the AuLi3@Ni foam current collector based LMAs can run for 740 h without cell failure in a symmetric cell. Furthermore, the Li-AuLi3@Ni foam|LiFePO4 full cell shows an excellent capacity retention of 43.8% with a high CE of 99.2% at 1C for 500 cycles. This work further illustrates the critical importance of surface lithiophilicity in guiding lithium cycling and suggests engineering the skeleton surface of commercial metal foam current collectors is important to improve 3D structured LMAs.

The NiS2 nanosheet array on Ni foil (NiS2/NF) was prepared using an in situ growth strategy and sulfidation method and was used as the cathode of lithium sulfur battery. The unique nanostructure of the NiS2 nanosheet array can provide abundant active sites for the adsorption and chemical action of polysulfides. Compared with the sulfur powder coated pure NF (pure NF-S) for lithium sulfur battery, the sulfur powder coated NiS2/NF (NiS2/NF-S) electrode exhibits superior electrochemical performance. Specifically, the NiS2/NF-S delivered a high reversible capacity of 1007.5 mAh g−1 at a current density of 0.1 C (1 C= 1675 mA g−1) and kept 74.5% of the initial capacity at 1.0 C after 200 cycles, indicating the great promise of NiS2/NF-S as the cathode of lithium sulfur battery. In addition, the NiS2/NF-S electrode also showed satisfactory electrochemical performance when used as the cathode for sodium sulfur battery.

Nanocomposites LiMnxFe1-xPO4/C (x = 1, 5/6, 2/3, 1/2) are synthesized by a sol-gel route combined with freeze drying. Fe2+ substituted samples coated by high-ordered carbon have the same olivine structure of LiMnPO4/C but reduced cell volumes. Fe2+ substituting greatly influences magnetic characteristics of LiMnPO4/C and slight amounts of Fe2P impurity in Fe2+ doped samples are verified by magnetic tests. Fe2+ substituted samples exhibit much better electrochemical properties. Among them, LiMn1/2Fe1/2PO4/C displays the best rate capacity and cyclic stability. Its initial discharge capacity reaches 140.1 mAh g−1 and remains at 132.5 mAh g−1 after 100 cycles at 2C, remarkably higher than those of LiMnPO4/C. The superior electrochemical performances are mainly attributed to small charge-transfer impedance, fast Li+ diffusion, residual carbon and existence of Fe2P with excellent electronic conductivity.

With the increasing demand for high energy and power energy storage devices, lithium metal batteries have received widespread attention. Li metal has long been regarded as an ideal candidate for negative electrode due to its high theoretical specific capacity (3860 mAh g−1) and low redox potential (-3.04 V vs. standard hydrogen electrode). However, notorious dendrite, low coulombic efficiency (CE), fast electrolyte consumption, large volume change and formation of “dead lithium” during cycling hinder its practical applications for decades. In order to address these issues and improve the electrochemical performance and safety of lithium metal batteries, tuning the lithium deposition via structuring a host for Li metal anode has been widely recognized as an efficient method. Thus, this paper overviews the recent progress in engineering Li host structure, with the focus on different approaches and design criteria. In the end, the perspectives for boosting the practical application of Li metal negative electrode are also proposed.

LiNi0.5Mn1.5O4 is a promising cathode material for high power lithium ion batteries (LIBs) for electric vehicles (EVs) and hybrid electric vehicles (HEVs). For the first time we design a tri-functional coating to improve the cycling performance of LiNi0.5Mn1.5O4. With the designed BiPO4 coating, the capacity retentions of LiNi0.5Mn1.5O4 are largely improved from 84.3% to 93.6% at 0.5 C after 50 cycles and from 80.6% to 96.2% at 10 C after 100 cycles. The tri-functional coating reduces the charge transfer resistance of LiNi0.5Mn1.5O4 cathode and plays a critical role in enhancing the electrochemical performance and lifetime. This strategy provides a new way to modify electrode materials to elevate the performance of LIBs.

The increasing demand for portable electronic devices and hybrid electric vehicles stimulates the development of supercapacitors as an advanced energy storage system. Here, we demonstrate a binder-free nickel hydroxide@nanoporous gold/Ni foam (Ni(OH)2@NPG/Ni foam) electrode for high-performance supercapacitors, which is prepared by a facile three-step fabrication route including electrodeposition of Au-Sn alloy on Ni foam, chemical dealloying of Sn and electrodepostion of Ni(OH)2 on NPG/Ni foam. Such Ni(OH)2@ NPG/Ni foam electrode is composed of a thin layer of conformable Ni(OH)2 nanoflakes supported on three-dimensional (3D) hierarchically porous NPG/Ni foam substrate. The resulting Ni(OH)2@NPG/Ni foam electrode can offer highways for both electron transfer and ion transport and lead to an excellent electrochemical performance with an ultrahigh specific capacitance of 3,380 F g–1 at a current density of 2 A g–1. Even when the current density was increased to 50 A g–1, it still retained a high capacitance of 1,927 F g–1. The promising performance of the Ni(OH)2@NPG/Ni foam electrode is mainly ascribed to the 3D hierarchical porosity and the highly conductive network on the NPG/Ni foam composite current collector, as well as the conformal electrodeposition of Ni(OH)2 active material on the NPG/Ni foam, which induces the formation of interconnected porosity both on the top surface and on the inner surface of the electrode. This inspiring electrochemical performance would make the as-designed electrode material become one of the most promising candidates for future electrochemical energy storage systems.

Lithium metal batteries (LMBs) have received extensive attention and research interest as high specific energy systems. However, the issues of Li dendrites growth in LMBs restrict their practical applications. The development of lithiophilic collectors can effectively solve the issues of Li dendrites growth. This study reports excellent lithium storage performance of lithiophilic nanosheet arrays which consist of electronic conductor Ni and ionic conductor Li2O (Ni-LONSs) on Ni foil (NF) fabricated via a simple preparation method for LMBs. The ionic conductor Li2O of the Ni-LONSs layer is lithiophilic and can induce uniform Li deposition on the Ni-LONSs collector. In addition, the nanosheet array structure of the Ni-LONSs collector is beneficial to slow down the volume change of the Li plating/stripping. In comparison with the NF collector, due to the specific nanosheet array structure of Ni-LONSs collector, the Ni-LONSs collector demonstrates excellent coulombic efficiency of 97.2% after 280 cycles (95.7% after 100 cycles of NF collector) and satisfactory cycling lifespan of 340 h (about 120 h of NF collector) at 0.5 mA cm-2with 1.0 mAh cm-2. Furthermore, the Ni-LONSs collector shows superior electrochemical performance in Ni-LONS/Li∣LiFePO4full cells. The excellent lithium storage performance of Ni-LONSs collector with mixed ionic/electronic conductor is conducive to the development and practical applications of LMBs.

Biomass walnut shell was used to prepare activated carbon (AC) through a carbonization treatment and an activation procedure with potassium hydroxide (KOH). AC showed hierarchical pores: 0.6 nm micropores, 2.7 nm mesopores and macropores with average diameter of 50 nm, providing a large specific surface area of 2318 m 2 g −1 . This highly porous AC was tested as a host material to encapsulate sulfur via a vapor phase infusion process. The developed AC-S electrode showed a high initial specific capacity of 1350 mAh g −1 and good capacity retention over 100 cycles at 0.1 C for lithium–sulfur battery.

Lithium–sulfur batteries with a high energy density are promising energy storage devices. The realization of lithium–sulfur batteries is mainly hindered by the dissolution of the intermediate polysulfides. In the present work, a new physical and chemical entrapment method of the polysulfides has been proposed, which used CMK-3 as the carbon scaffolds and a MnO 2 coating layer for chemisorption. Such a bi-functional framework provides efficient trapping for the polysulfides, achieving a reversible capacity of 600 mAh g −1 after 100 cycles at 0.1 C with a 73.4 wt% sulfur loading in the composite.

Using electrical vehicles instead of traditional ones is very important for reducing fossil oil consumption and carbon emissions. Spinel LiNi0.5Mn1.5O4 is considered as a promising cathode material for advanced lithium ion batteries owing to its high power density. Nevertheless, it suffers badly from the interfacial reactions with the electrolyte at high operation potential, which degrades its electrochemical performance. The strategy of the present study is to prevent direct contact between LiNi0.5Mn1.5O4 and the electrolyte by using a surface coating in order to reduce solid electrolyte interfacial reactions and consequently enhance its cycling performance. The experimental results indicated that as-prepared LiNi0.5Mn1.5O4 sintered at 900 °C possessed the highest initial specific capacity of 132.4 mA h·g−1 at 0.2 C rate, with 81.0% initial capacity retention after 50 cycles. Coating AlF3 on the particle surfaces of LiNi0.5Mn1.5O4 using a modified solid-state method can improve its electrochemical properties by enhancing its initial specific capacity from 104.6 to 109.1 mA h·g−1 and increasing its capacity retention from 80.6 to 92.1% at the 10 C rate after 100 cycles.

The application of grafted membranes based on modified poly(ethylene-alt-tetrafluoroethylene) (ETFE) in redox flow-batteries is reported. In analogy to commercial Nafion® 117 based membranes ETFE backbone material provides chemical, thermal, and mechanical stability. Side chains composed of 2-hydroxyethyl methacrylate (HEMA) and glycidyl methacrylate (GMA) grafted to ETFE were sulfonated to achieve the required proton exchange capacity. Application in a vanadium based redox flow-battery demonstrates the applicability of this kind of membranes for energy storage systems. The degree of grafting was identified as the key parameter to tune the membrane properties.

Lithium metal anodes (LMAs) are critical for high-energy-density batteries such as Li-S and Li-O2 batteries. The spontaneously formed solid electrolyte interface on LMAs is fragile, which may not accommodate the cyclic Li plating/stripping. This usually will result in a low coulombic efficiency (CE), short cycle life, and potential safety hazards induced by the uncontrollable growth of lithium dendrites. In this study, we fabricate a Li alginate-based artificial SEI (ASEI) layer that is chemically stable and allows easy Li ion transport on the surface of LMAs, thus enabling the stable operation of lithium metal anodes. Compared to bare LMAs, the ASEI layer-protected LMAs exhibit a more stable Li plating/stripping behavior and present effective dendrite suppression. The symmetric Li∥Li cells with the ASEI layer-protected LMAs can stably run for 850 and 350 h at current densities of 0.5 and 1 mA cm-2, respectively. Additionally, the LiFePO4∥Li full cell with the ASEI layer-protected LMA exhibits a capacity retention of about 94.0% coupled with a CE of 99.6% after 1000 cycles at 4 C. We believe that this study of engineering an ASEI brings a new and promising approach to the stabilization of LMAs for high-performance lithium metal batteries.

A multifunctional coating with high ionic and electronic conductivity is constructed on the surface of LiNi0.8Co0.1Mn0.1O2 (NCM) to boost the battery stability upon cycling and during storage as we...

A major source of capacity fade of the common vanadium redox flow battery (VRFB) is the vanadium ion transport through the separator. However, different transport models disagree significantly in the diffusion coefficient for the different V species and the influence of different transport mechanisms. The underlying hypothesis of this work is that reactions inside the membrane are partly responsible for these discrepancies. Accordingly, it was investigated if redox reactions inside the nanoscopic water body of Nafion 117 can occur. X-ray absorption near edge structure spectroscopy (XANES) was used to distinguish between the different V species inside hydrated Nafion 117 and novel PVDF-based membranes. It was validated that the speciation of vanadium can be performed using the pre-edge peak energy and intensity. The experiments were performed as follows: strips of the membrane were exposed from one site to a V3+ solution (green) and from the other site to a VO2+ solution (yellow). The ions could diffuse into the membrane from both sides. A change of color of the membrane strip was observed. The blue color in the middle of the strip indicated that VO2+ was formed where V3+ and VO2+ got in contact. Using XANES this reaction inside Nafion was proven.

We have successfully prepared 6.5 nm palladium tin (PdSn) alloy nanoparticles (NPs) with tunable compositions by high-temperature reduction of tin acetate and palladium bromide in the presence of oleylamine and trioctylphosphine. The catalytic activities of PdSn NPs with different compositions were evaluated through Suzuki reactions. The PdSn nanocatalysts show better catalytic activity on Suzuki reactions than an equal amount of pure Pd NPs, and their catalytic activities are highly composition dependent. Among these NPs, Pd63Sn37/C NPs exhibited the highest catalytic performance with higher reaction activity, lower Pd leaching properties, and higher stability even after eight recycle reactions.

Flexible lithium sulfur batteries are promising power sources for the next generation wearable electronics, due to their high energy density and low cost. Here, we demonstrate a metal current collector-free, binder-free, flexible sulfurized polyacrylonitrile film electrode with hollow tubular nanofibers (H-SPAN), which is fabricated via coaxial electrospinning and a simple heat treatment. The all-fibrous films H-SPAN not only provides three-dimensional continuous electron and ion transport paths, but also suppresses the shuttle effect, contributing to better redox kinetics, cycling performance, and flexibility. The H-SPAN film electrode delivers a high specific lithium storage capacity of 1250 mAh g−1sulfur or 514.75 mAh g−1electrode at 0.1C with stable cycling over 300 cycles. Additionally, when H-SPAN is applied as a cathode for room temperature Na–S batteries, it also exhibits superb capacity and cycling stability (717 mAh g−1sulfur or 295.2 mAh g−1electrode at 0.1C after 200 cycles). The working mechanism of H-SPAN is well elucidated by ex situ Raman spectroscopy and ex situ X-ray Photoelectron Spectroscopy (XPS). The excellent flexibility of the H-SPAN film electrode lends itself well to potential applications in wearable electronic devices.

Rechargeable lithium metal anodes (LMAs) with long cycling life have been regarded as the "Holy Grail" for high-energy-density lithium metal secondary batteries. The skeleton plays an important role in determining the performance of LMAs. Commercially available copper foam (CF) is not normally regarded as a suitable skeleton for stable lithium storage owing to its relatively inappropriate large pore size and relatively low specific surface area. Herein, for the first time, we revisit CF and address these issues by rationally designing a highly porous copper (HPC) architecture grown on CF substrates (HPC/CF) as a three-dimensional (3D) hierarchically bicontinuous porous skeleton through a novel approach combining the self-assembly of polystyrene microspheres, electrodeposition of copper, and a thermal annealing treatment. Compared to the CF skeleton, the HPC/CF skeleton exhibits a significantly improved Li plating/stripping behavior with high Coulombic efficiency (CE) and superior Li dendrite growth suppression. The 3D HPC/CF-based LMAs can run for 620 h without short-circuiting in a symmetric Li/Li@Cu cell at 0.5 mA cm

We have developed a novel one-pot synthetic procedure for monodisperse palladium tin bimetallic alloy nanoparticles (NPs) with tunable compositions and sizes by the co-reduction of tin(II) acetate and palladium(II) bromide in the presence of oleylamine and trioctylphosphine. These NPs loaded on active carbon (PdSn/C) were used as active catalysts for Heck reactions, and exhibited composition dependent catalytic activities. Among these nanocatalysts, Pd63Sn37 NPs showed the best catalytic performance which is even superior to pure Pd NPs. PdSn NPs with controlled compositions and sizes were synthesized and characterized systematically, and Pd63Sn37/C NPs showed the best catalytic ability and stability that is even superior to pure Pd NPs with higher catalytic activity and stability in multi-recycled Heck reactions.

Composition controllable monodisperse palladium tin nanoparticles (Pd x Sn 100−x NPs, x = 77, 69, 63, 52, 49) were prepared by the thermal reduction of palladium bromide and tin acetate in the presence of trioctylphosphine and oleylamine. The NPs were investigated for their catalytic abilities of hydrogen generation from hydrolysis of ammonia borane complex. Deposited on a carbon support without any further treatment, these NPs were active nanocatalysts for hydrolysis of ammonia borane complex, and their catalytic activities were highly composition dependent. Among these NPs studied, Pd 69 Sn 31 NPs exhibited the highest catalytic activity and stability under mild reaction conditions. Kinetic investigations showed that the catalytic hydrolysis of ammonia borane was first-order with respect to catalyst concentration and zero-order with respect to ammonia borane concentration. The activation energy for the hydrolysis of ammonia borane complex in the presence of Pd 69 Sn 31 NPs was calculated to be 27.22 kJ mol −1 . The Pd x Sn 100−x NPs are promising candidates toward the practical development of the ammonia borane complex as a feasible hydrogen storage medium for fuel cell applications under ambient conditions.

A hybrid structure of nanoporous gold (NPG) on three-dimensional (3D) macroporous Ni foam has been synthesized by electrodeposition of Au–Sn alloy film followed by a facile chemical dealloying process under free corrosion conditions. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to characterize the morphology and structure of the NPG/Ni foam hybrids. It is shown that the Ni foam skeletons are uniformly wrapped by the NPG film which is composed of bicontinuous nanostructures consisting of interconnected ligaments and nanopores. Electroreduction of H 2 O 2 on the NPG/Ni foam hybrid electrode in acid media is investigated by linear scan voltammetry, chronoamperometry and electrochemical impedance spectroscopy. It is found that such hierarchical porous electrode displays superior activity, durability and mass transport property for H 2 O 2 electroreduction. These results demonstrate the potential of the NPG/Ni foam hybrid electrodes for the applications in fuel cell technology.

The electrochemical quartz crystal microbalance (EQCM) and density functional theory (DFT) have been combined to study the special reaction between thiourea (TU) and metal cluster and the mechanism of the replacement of Cu by Sn in the presence of TU for the first time. The natural bond orbital (NBO) charge of the top copper atom obviously shifts toward positive values compared to the interaction behavior of single and double (S=C) regions with Cu4 cluster via the DFT method. This can explain the reason for the accelerating corrosion process at higher TU concentrations since the copper atoms can change to cuprous ions in this process. It is proven that the thermodynamically impossible replacement of Cu by Sn can occur in the presence of TU by reducing the OCP of the copper electrode to a more negative value than the redox potential of Sn 2+ /Sn. The DFT investigation on the interactions between delocalization (S=C) and (N-C) regions in TU and Cu 4 or Sn 4 cluster indicates that the highest molecular occupied orbital (HOMO) of the S=C region has better than adequate to the lowest unoccupied molecular orbital (LUMO) of Cu4 cluster than that of Sn 4 cluster. The replacement mechanism deduced based on the first-principles analysis is universally applicable to the alloy deposition, corrosion inhibition, and surface treatment.

An organic–inorganic hybrid polymeric complex, [BaPt(NCS)4(C20H36O6)(H2O)] n or [[Ba(DC18C6-A)(H2O)][Pt(SCN)4]] n (1) (DC18C6-A = cis-syn-cis-dicyclohexyl-18-crown-6) has been synthesized by the reaction of cis-syn-cis-dicyclohexyl-18-crown-6 with Ba(SCN)2, BaCO3 and H2PtCl4, and characterized by elementary analysis, FT-IR spectra and X-ray single-crystal diffraction. It crystallizes as monoclinic, space group P 21/n with crystallographic data: a = 14.275(6) A, b = 13.165(5) A, c = 18.971(8) A, β = 106.294(6)°, V = 3422(2) A3, Z = 4, D calcd = 1.854 g/cm3, F(000) = 1856, R 1 = 0.0491, wR 2 = 0.0709. The asymmetric unit of complex 1 contains one [Ba(DC18C6-A)(H2O)]2+ complex cation and one [Pt(SCN)4]2− complex anion, which are assembled into an infinite polymeric chain via the bridging SCN groups. The coordinated water molecule gives two different intrachain and interchain hydrogen bonds.

Reactions of N15C5 (2,3-naphtho-15-crown-5) with nickel maleonitriledithiolate sodium complex, Na2[Ni(mnt)2] (mnt = maleonitriledithiolate) using different molar ratios (2 : 1 and 4 : 1) afforded two structurally different complexes [Na(N15C5)2]2[Ni(mnt)2] (1) and [Na(N15C5)]2[Ni(mnt)2] (2). The sandwich [Na(N15C5)2]+ and mono-capped [Na(N15C5)]+ organic cations are observed in the crystals of 1 and 2, respectively, with the same [Ni(mnt)2]2− inorganic conteranions. It is these structurally different organic cations that lead to the dissimilar structures. Complex 1 exhibits a one-dimensional (1D) chain-like structure assembled by intercantionic {[Na(N15C5)2]+}∞ π–π stacking interactions and electrostatic interactions, while 2 displays a novel two-dimensional (2D) corrugated sheet-like structure constructed by Na–N interactions which occur between the [Na(N15C5)]+ inorganic cations and [Ni(mnt)2]2− inorganic anions.

A novel supramolecular complex, [Na2(2,3-naphtho-15-crown-5)2(NO3)][Cu(NO3)3(H2O)] (1), has been prepared and characterized by X-ray single crystal diffraction. The complex crystallizes in the triclinic system, space group Pī, with a = 11.233(6), b = 13.342(7), c = 16.601(8) A, α = 89.836(7), β = 79.132(8), γ = 66.545(7)°, V = 2234(2) A3, Z = 2 and final R 1(wR 2) = 0.0467(0.1164). Novel coordination features and supramolecular architectures are found in the solid state of 1. Two [Na(2,3-naphtho-15-crown-5)]+ cations containing two different sodium coordination numbers (six and seven) are bridged by a tridentate nitrate group, to form a larger complex cation, [Na2(2,3-naphtho-15-crown-5)2(NO3)], which is assembled into a novel 1D zigzag chain-like structure through aromatic C–H ··· π interactions.

Two inorganic‐organic hybrid complexes [Na(DC18C6‐A)]2[Pd(mnt)2] (1), and [Na(DC18C6‐A)]2[Pt(mnt)2] (2) (DC18C6‐A=cis‐syn‐cis‐dicyclohexyl‐18‐crown‐6, isomer A; mnt=maleonitriledithiolate) have been obtained by the reaction of dicyclohexyl‐18‐crown‐6 with Na2mnt and PdCl2 or K2PtCl4. Their compositions and crystal structures are characterized by elementary analysis, FT‐IR, UV‐Vis spectroscopy and x‐ray single crystal diffraction. They both crystallize triclinic, space group P ī with crystallographic data: 1, a=10.283(6) A, b=11.683(7) A, c=12.681(8) A, α=100.566(8)°, β=109.686(7)°, γ=100.733(8)°, V=1358.5(14) A3, Z=1, Dcalcd=1.440 g/cm3, F(000)=616, R 1=0.0290, wR 2=0.0676. 2, a=10.289(6) A, b=11.691(7) A, c=12.679(7) A, α=100.495(8)°, β=109.762(8)°, γ=100.886(8)°, V=1358.6(14) A3, Z=1, Dcalcd=1.548 g/cm3, F(000)=648, R 1=0.0325, wR 2=0.0514. The two complexes are isomorphous and both display an infinite 1D chain‐like structure formed by [Na(DC18C6‐A)]+ complex cations and [M(mnt)2]2− (M=Pd, Pt) complex a...

The reactions of 2,3-naphtho-15-crown-5 (N15C5) with Na2[Pt(L)2] [L=1,2-dicyanoethylene-1,2-dithiolate (mnt) or 1,1-dicyanoethylene-2,2-dithiolate (i-mnt)] afford two complexes [Na(N15C5)2]2[Pt(mnt)2] (1) and [Na(N15C5)]2[Pt(i-mnt)2] (2). They are characterized by elemental analysis, FT-IR, UV–visible spectra and single crystal X-ray diffraction. 1 crystallizes in the monoclinic, space group P21/c with a=15.616(11), b=20.481(14), c=12.910(9) A, β=103.298(11)°, V=4018(5) A3, Z=2 and R1(wR2)=0.0390 (0.0808). 2 crystallizes in the triclinic, space group Pī with a=8.360(3), b=12.892(5), c=12.899(5) A, α=115.472 (5), β=106.053(6)°, γ=91.981(6)°, V=1187.2(8) A3, Z=1 and R1(wR2)=0.0365 (0.0775). The [Na(N15C5)2]+ sandwich complex cations of 1 are assembled into a novel 1D zigzag chain by alternating π–π stacking interactions and the resulting cationic chains are linked into a 2D network by the bridging [Pt(mnt)2]2− complex anions through weak C–H⋯S hydrogen bonds. For 2, the [Na(N15C5)]+ mono-capped complex cations act as the bridges linking the [Pt(i-mnt)2]2− anions into a 1D infinite chain through Na–N bonds and S⋯C and S⋯π interactions are observed in the chain.

A facile process was developed for the synthesis of graphene-supported TiO2 (B) nanosheets (GTBN) composite based on the hydrothermal treatment titanium (III) chloride and graphene oxide in an ethylene glycol. The morphology and microstructure of the composites were examined by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectroscopy. The obtained GTBN show a high thermal stability and the phase transformation of TiO2 (B) to anatase can be prevented by graphene after pyrolysis of GTBN at 350 °C for 2 h. Furthermore, GTBN exhibited high rate performance and stability of lithium ion batteries, due to the enhanced conductivity of the electrode and accommodation to volume/strain changes during lithium insertion–extraction.

We report a novel strategy for the fabrication of nanoporous gold (NPG) films. The fabrication process involves the electrodeposition of a gold-tin alloy, followed by subsequent chemical dealloying of tin. Scanning electron microscopy (SEM) images show a bicontinuous nanoporous structure formed on the substrates after chemical dealloying. Energy dispersive x-ray (EDX) analysis indicates that there are no impurities in the Au-Sn alloy film with an average composition of 58 at. % Au and 42 at. % Sn. After dealloying, only gold remains in the NPG film indicating the effectiveness of this technique. X-ray diffraction (XRD) results reveal that the as-prepared Au-Sn alloy film is composed of two phases (Au5Sn and AuSn), while the NPG film is composed of a single phase (Au). We demonstrate that this approach enables the fabrication of NPG films, either freestanding or supported on various conductive substrates such as copper foil, stainless steel sheet and nickel foam. The resulting NPG electrode exhibits enhanced electrocatalytic activity toward both H2O2 reduction and methanol oxidation compared to the polished Au disc electrode. Our strategy provides a general method to fabricate high quality NPG films on conductive substrates, which will broaden the application potential of NPG or NPG-based materials in various fields such as catalysis, optics and sensor technology.

The title polymeric complex, [PbPd(NCS)4(C20H36O6)(H2O)]n or {[Pb(DC18C6-A)(H2O)][Pd(SCN)4]}n (DC18C6-A = cis-syn-cis-dicyclo­hexyl-18-crown-6), has been synthesized by the reaction of dicyclo­hexyl-18-crown-6 with PdCl2 and Pb(SCN)2. The SCN groups bridge [Pb(DC18C6-A)(H2O)]2+ complex cations and [Pd(SCN)4]2− complex anions to form infinite polymeric chains.

A facile, rapid, selective and sensitive colorimetric method for the detection of copper ions (Cu2+) based on anti-aggregation of the glutathione-induced aggregated gold nanoparticles (AuNPs) was developed. Cu2+ can prevent the aggregation of AuNPs induced by glutathione (GSH) through catalyzing oxygen oxidation of GSH to oxidized glutathione (GSSG). In the presence of a specified amount of GSH, the aggregations of AuNPs decrease with increasing concentrations of Cu2+, which can be monitored by an ultraviolet-visible spectrophotometer or the naked eye. High sensitivity could be achieved for the detection of Cu2+ down to 20 nM. The method shows excellent selectivity toward Cu2+ over other metal ions, which can not prevent the GSH-induced aggregation of AuNPs even at a 20-fold molar excess. We further used the proposed method to selectively and sensitively detect sulfide anions in aqueous solution. The detection limit of sulfide anions (S2−) could reach 100 nM, which is one order of magnitude lower than that of GSH modified AuNPs-based colorimetric S2− assay.

Electrical Vehicles (EVs) are very important in reducing fossil oil consumption and carbon emission in cities. Spinel LiNi 0.5 Mn 1.5 O 4 is one promising cathode material for lithium ion batteries used in EVs owing to its high power density. Here AlF 3 coated LiNi 0.5 Mn 1.5 O 4 is prepared through an newly developed method. The spinel oxide sintered at 900 C presents the best electrochemical performance with a specific discharge capacity of 132.4 mAh/g at 0.5 C. 81.0% of the initial specific capacity can be retained after 50 cycles. AlF 3 coating can further improve the electrochemical performance. The initial specific capacity at 10 C is enhanced from 104.6 to 109.1 mAh g -1 with the capacities retention increasing from 80.6 to 92.1% after 100 cycles.