A novel all-solid-state thin-film-type lithium-ion battery with in situ prepared positive and negative electrode materials

A novel all-solid-state thin-film-type rechargeable lithium-ion battery employing in situ prepared both positive and negative electrode materials is proposed. A lithium-ion conducting solid electrolyte sheet of Li₂O–Al₂O₃–TiO₂–P₂O₅-based glass–ceramic manufactured by OHARA Inc. (OHARA sheet) was used as the solid electrolyte, which was sandwiched by Cu and Mn metal films. The Cu/OHARA sheet/Mn layer became an all-solid-state lithium-ion battery after applying d.c. 16 V to the layer, and the resultant battery operated at 0.3–0.8 V with reversible capacity of 0.45 μAh cm^?2. High voltage battery was successfully prepared by applying the d.c. high voltage to a five-series of Cu/OHARA sheet/Mn layer, resulting in all-solid-state battery operating at 1.5–4.0 V. The proposed fabrication process will become a new technology to develop advanced all-solid-state rechargeable lithium-ion batteries.     

Electrodeposition of CuInSe2 films by an alternating double-potentiostatic method using nearly neutral electrolytes

One step electrodeposition with an alternating double-potentiostatic(DPSED) program was used to prepare CuInSe₂ thin films in nearly neutral aqueous electrolytes with sodium citrate complex. Linear sweep voltammetry(LSV) was measured to probe voltammetric properties of electrolytes with respect to Cu, In and Se individual precursor and their mixed solutions. Compositional and structural characteristics of the as-deposited and annealed films at 400 °C in Ar atmosphere for 0.5 h were analyzed by XRD and XPS. The results showed that reduction of Cu²⁺ to Cu⁺ at one potential point of ?800 mV and subsequently formation of CuIn alloy as well as metal In and amorphous Se at the other potential point of ?1400 mV were responsible for synthesis of CISe chalcopyrite. Composition self-regulation made DPSED films have three elements co-deposition and more uniform element distribution, which promoted chalcopyrite CISe formation.     

Chemically stable anode-supported solid oxide fuel cells based on Y-doped barium zirconate thin films having improved performance

Anode-supported solid oxide fuel cells (SOFCs) based on thin BaZr_0.8Y_0.2O_3 ? δ (BZY) electrolyte films were fabricated by pulsed laser deposition (PLD) on sintered NiO–BZY composite anodes. After in situ reduction of NiO to Ni, the anode substrates became porous, while retaining good adhesion with the electrolyte. A slurry-coated composite cathode made of La_0.6Sr_0.4Co_0.2Fe_0.8O_3 ? δ (LSCF) and BaCe_0.9Yb_0.1O_3 ? δ (BCYb), specifically developed for proton conducting electrolytes, was used to assemble fuel cell prototypes. Depositing by PLD 100 nm thick LSCF porous films onto the BZY thin films was essential to improve the cathode/electrolyte adhesion. A power density output of 110 mW/cm² at 600 °C, the largest reported value for an anode-supported fuel cell based on BZY at this temperature, was achieved. Electrochemical impedance spectroscopy (EIS) measurements were used to investigate the different contributions to the total polarization losses.     

Synthesis of L10 Fe–Pd films by electrodeposition and thermal annealing

Fe–Pd alloy films have been prepared by electrochemical deposition from an alkaline electrolyte containing Fe sulfate, Pd chloride and 5-sulfosalicylic acid onto polycrystalline titanium substrates. The as-deposited films were nanocrystalline and magnetically soft (coercivity ∼ 25 Oe). L1₀ Fe–Pd films with a (1 1 1) preferred orientation were obtained by post-deposition thermal annealing of films with composition about 37 at% Fe in an (Ar + 5% H₂) gas flow at 500 °C. Such films exhibit hard magnetic properties, with a coercivity up to 1880 Oe, and a slightly anisotropic magnetic response, with a larger in-plane remanence. Preliminary magnetic investigations support magnetization switching through pinning of domain walls.     

Structures and magnetic properties of one-dimensional copper(II) complexes bridged with diazaaromatic rings

Seven kinds of polynuclear complexes of [Cu(hfac)₂] (Hhfac = 1,1,1,5,5,5-hexafluoropentane-2,4-dione) with diazaaromatic rings have been prepared. The crystal structures of [{Cu(hfac)₂(μ-L)}_n] (L = 2,5- and 2,6-dimethylpyrazines, propylpyrazine (prpyz), quinoxaline, phenazine, 4,6-dimethylpyrimidine, and 1,6-naphthyridine) have been determined. These complexes consist of a one-dimensional chain structure, and the geometry around the copper ion is approximately an octahedral structure. The relations between the magnetic properties and coordination structure were discussed from the magnetic measurements. In the μ-prpyz complex, one nitrogen atom is coordinated to a copper ion at an axial position, and at the same time the other coordinated at an equatorial site of a neighboring copper ion. This complex showed antiferromagnetic interaction with J/k_B = −0.086(3) K estimated from the Bonner–Fisher model. Weak magnetic interaction is caused by the somewhat long Cu–N distances due to the steric effect from the bridging ligands.     

Direct electrochemistry of hemoglobin and glucose oxidase in electrodeposited sol–gel silica thin films on glassy carbon

This work points out that electrogeneration of silica gel (SG) films on glassy carbon electrodes (GCEs) can be applied to immobilize biomolecules – hemoglobin (Hb) or glucose oxidase (GOD) or both of them in mixture – without preventing their activity. These proteins were physically entrapped in the sol–gel material in the course of the electro-assisted deposition process applied to form the thin films onto the electrode surface. SG films were prepared from a precursor solution by applying a suitable cathodic potential likely to induce a local pH increase at the electrode/solution interface, accelerating thereby polycondensation of the silica precursors with concomitant film formation. Successful immobilization of proteins was checked by various physico-chemical techniques. Both Hb and GOD were found to undergo direct electron transfer, as demonstrated by cyclic voltammetry. GCE–SG–Hb gave rise to well-defined peaks at potentials E_c = −0.29 V and E_a = −0.17 V in acetate buffer, corresponding to the Fe^III/Fe^II redox system of heme group of the protein, while GCE–SG–GOD was characterized by the typical signals of FAD group at E_c = −0.41 V and E_a = −0.33 V in phosphate buffer. These two redox processes were also evidenced on a single voltammogram when both Hb and GOD were present together in the same SG film. Hb entrapped in the silica thin film displayed an electrocatalytic behavior towards O₂ and H₂O₂ in solution, respectively in the mM and μM concentration ranges. Immobilized GOD kept its biocatalytic properties towards glucose. Combined use of these two proteins in mixture has proven to be promising for detection of glucose in solution via the electrochemical monitoring of oxygen consumption (decrease of the oxygen electrocatalytic signal).     

Lithium antimonite: A new class of anode material for lithium-ion battery

LiSbO₃ has been synthesized by chemical mixing followed by thermal treatment at 800 °C. Field emission scanning electron microscopy revealed bar shaped multifaceted grains, 0.5–4 μm long and 0.5–1 μm wide, that cluster together as soft agglomeration. 2032 type coin cell vs Li/Li⁺ shows a flat charge–discharge plateau together with low Li intercalation/de-intercalation potential (0.2/0.5 V). A high discharge capacity of 580 mA h g^?1 has been obtained in the 1st cycle with 100% Coulombic efficiency. About 96% of the Coulombic efficiency is retained up to the 12th cycle, but at the 15th cycle, the Coulombic efficiency drops down to 88%. AC impedance spectroscopy shows an increase in electrolyte resistance (R_s) from 4.43 Ohm after the initial cycle to 12.4 Ohm after the 15th cycle indicating a probable dissolution of Sb into the electrolyte causing the capacity fading observed.     

Coordination polymers incorporating copper(II) and manganese(II) centers bridged by pyridinedicarboxylate ligands: Structure and magnetism

Two heterobimetallic coordination polymers, [Cu(2,4-pydc)₂Mn(H₂O)₄]_x (1) and [Cu(2,5-pydc)₂Mn(H₂O)₂]_x · 4xH₂O (2), have been synthesized and structurally characterized by single crystal X-ray diffraction. Both compounds have extended 2-D sheet structures. In 1 the copper centers are linked in chains by double ligand bridges and these chains are cross-linked through the manganese coordination spheres and O–C–O bridges to form polymeric sheets. In 2 separate O–C–O bridged Cu and Mn chains are connected in an alternating array by additional ligand bridging to generate the overall 2-D structure. Analysis of magnetic data of 1 reveals that ferromagnetic exchange between the O–C–O bridged copper and manganese centers dominates the magnetic properties of this system. The magnetic data for 2 fit well to a model incorporating antiferromagnetic exchange in independent S = 1/2 and S = 5/2 linear chains with J(Cu) = −0.073 cm⁻¹ and J(Mn) = −0.32 cm⁻¹. Unlike the situation in 1, there is no evidence for heterometallic exchange. In both 1 and 2 the significant exchange occurs via O–C–O bridges. To study the effect of thermal dehydration on the magnetic properties of these systems, the compounds Cu(2,4-pydc)₂Mn · H₂O (1d) and Cu(2,5-pydc)₂Mn · H₂O (2d) were synthesized and studied.     

Composite cathode for IT-SOFC: Sr-doped lanthanum cuprate and Gd-doped ceria

Composite cathodes were synthesized via a citrate combustion method followed by an organic precipitation method. The cathodes were of K₂NiF₄-type crystal structure with x wt.% Ce_0.9Gd_0.1O_1.95 (CGO)–(100 ? x) wt.% La_1.96Sr_0.04CuO_4 + δ (LSC), where x = 0, 10, 20 and 30. The individual structural phases of the composite cathodes were characterized using a third-generation synchrotron source beamline powder X-ray diffractometer (XRD). The porous grain morphology of the CGO–LSC cathode composite for a symmetrical half-cell was determined from cross-sectional scanning electron microscopy images and elemental line profiles. The composite cathode was made of 20 wt.% CGO–80 wt.% LSC (CL20–80) and was coated onto a Ce_0.9Gd_0.1O_1.95 electrolyte. It showed the lowest area specific resistance (ASR) of 0.07 Ω cm² at 750 °C. An electrolyte-supported (300 μm thick) single-cell configuration of CL20–80/CGO/Ni-CGO attained a maximum power density of 626 mW cm^? 2 at 700 °C. The unique composite composition of CL20–80 demonstrates enhanced electrochemical performance and good chemical compatibility with the CGO electrolyte, as compared with the pure LSC (CL0–100) cathode for IT-SOFCs.     

Corrosion resistance of electroless Cu–P and Cu–P–SiC composite coatings in 3.5% NaCl

The Cu–P and Cu–P–SiC composite coatings on carbon steel substrates were deposited via electroless plating. The anti-corrosion properties of Cu–P and Cu–P–SiC coatings were studied in 3.5% NaCl solution. The anti-corrosion properties of Cu–P and Cu–P–SiC coatings were investigated in 3.5% NaCl solution by the weight loss, potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) techniques. It has been found that the shift in the corrosion potential (E_corr) towards the noble direction, decrease in the corrosion current density (I_corr), increase in the charge transfer resistance (R_ct) and decrease in the double layer capacitance (C_dl) values indicated an improvement in corrosion resistance with the incorporation of SiC particles in the Cu–P matrix. The effects of varying the SiC concentration on the corrosion resistance of carbon steel were investigated and it was found that the best anti-corrosion property of Cu–P–SiC is at 5 g L^?1 SiC in the bath formulation.     

Carbon based Si- and Cr-containing thin films: Chemical and nanomechanical properties

Si- and Cr-containing C films were deposited by magnetron sputtering combined with CVD onto silicon wafers. The composition and chemical structure were characterized by X-ray Photoelectron Spectroscopy (XPS) and nanomechanical properties by depth-sensing hardness and scratch techniques.The incorporated Si and Cr are preferentially bonded to carbon, in accordance with simplified thermodynamic calculations and as manifested by the XPS chemical shifts. At relatively high Cr- and low Si-content silicides (Cr_xSi) may also form as indicated by X-ray induced Auger electron spectroscopy. The chromium content in the C–Si–Cr films varied between 1 and 55 at% while the silicon content in the same films between 25 and 0 at%. For comparison two-component films of Si–C and Cr–C were also deposited with Si-content up to 42 at% and Cr-content up to 55 at% by varying the input power of the magnetrons.The nanohardness (H) and reduced modulus (E) were higher for all the films than that of the silicon substrate being 10 GPa, 127 GPa, respectively. Interestingly, the H and E of the three-component CrSiC films were almost invariant of the changes of the components' concentration within the indicated range and varied between 13–16 GPa and 120–140 GPa. H and E values for the two-component Cr–C films were much higher, reaching about 22 GPa and 170 GPa, respectively.     

Some transition metal ions complexes of tricine (Tn) and amino acids: pH-titration,synthesis and antimicrobial activity

Equilibrium studies have been carried out on complex formation of M(II) (M = Co(II), Cu(II) and Zn(II)) with tricine (Tn) and L = amino acids in aqueous solution, at 25 °C and ionic strength of I = 0.1 M (NaNO₃). The ternary complexes of amino acids are formed by simultaneous reactions. The concentration distribution of the complexes is evaluated. The solid complexes of [M(II)–Tn–Histidine (Hist)] have been synthesized and characterized by elemental analysis, infrared, magnetic and conductance measurements. The synthesized complexes have been screened for their antibacterial activities and the complexes show a significant antibacterial activity against four bacterial species: Staphylococcus aureus (Gram +ve), Streptococcus pyogenesr (Gram +ve), Serratia marcescens (Gram −ve) and Escherichia coli (Gram −ve). The activity increases by increasing the concentration of the complexes.     

Internal standardization in graphite furnace atomic absorption spectrometry: Comparative use of As and Ge to minimize matrix effects on Se determination in milk

Arsenic and germanium have been evaluated as internal standards to minimize matrix effects on the direct determination of selenium in milk by graphite furnace atomic absorption spectrometry (GFAAS) using tubes with integrated platform, pre-treated with W together with Pd as chemical modifier. The efficiency of As and Ge as internal standards for 25 μg L^− 1 Se plus 500 μg L^− 1 As or Ge in diluted (1 + 9 v/v) milk plus 1.0% (v/v) HNO₃ was evaluated by means of correlation graphs plotted from the normalized absorbance signals (n = 20) of internal standard (axis y) versus analyte (axis x). The equations that describe the linear regression were: A^As = − 0.004 ± 0.019 + 1.02 ± 0.019 A^Se (r = 0.9967 ± 0.005); A^Ge = − 0.017 ± 0.015 + 1.01 ± 0.015 A^Se (r = 0.9978 ± 0.004). Samples and reference solutions were automatically spiked with 500 μg L^− 1 Ge or As and 1.0% (v/v) HNO₃ by the autosampler. For 20 μL of aqueous standard solutions, analytical curves in the 5.00–40.0 μg L^− 1 Se range were established using the ratio of Se absorbance to internal standard absorbance (A^Se / A^IS) versus analyte concentration, and good linear correlations were obtained. The characteristic mass was 40 pg Se. Limits of detection were 0.55 and 0.40 μg L^− 1 with As and Ge as the internal standard, respectively. Relative standard deviations (RSD) for a sample containing 25 μg L^− 1 Se were 1.2% and 1.0% (n = 12) using As and Ge, respectively. The RSD without internal standardization was about 6%. The accuracy of the proposed method was evaluated by an addition-recovery experiment and all recovered values were in the 99–105% range with IS and in the 70–80% range without IS. Using Ge as the internal standard, results of analysis of standard reference materials were in agreement with certified values at a 95% confidence level. The selenium concentration for 10 analyzed milk samples varied from 5.0 to 20 μg L^− 1.     

Fe-doped SnO2 transparent semi-conducting thin films deposited by spray pyrolysis technique: Thermoelectric and p-type conductivity properties

In this paper, we report structural, electrical, optical, and especially thermoelectrical characterization of iron (Fe) doped tin oxide films, which have been deposited by spray pyrolysis technique. The doping level has changed from 0 to 10 wt% in solution ([Fe]/[Sn] = 0–40 at% in solution). The thermoelectric response versus temperature difference has exhibited a nonlinear behavior, and the Seebeck coefficient has been calculated from its slope in temperature range of 300–500 K. The Hall effect and thermoelectric measurements have shown p-type conductivity in SnO₂:Fe films with [Fe]/[Sn] ≥ 7.8 at%. In doping levels lower than 7.8 at%, SnO₂:Fe films have been n-type with a negative thermoelectric coefficient. The Seebeck coefficient for SnO₂:Fe films with 7.8 at% doping level has been obtained to be as high as +1850 μV/K. The analysis of as-deposited samples with thicknesses ～350 nm by X-ray diffraction (XRD) and scanning electron microscopy (SEM) has shown polycrystalline structure with clear characteristic peak of SnO₂ cassiterite phase in all films. The optical transparency (T%) of SnO₂:Fe films in visible spectra decreases from 90% to 75% and electrical resistivity (ρ) increases from 1.2 × 10^?2 to 3 × 10³ Ω cm for Fe-doping in the range 0–40 at%.     

Highly efficient electrogenerated chemiluminescence of natural chlorophyll a

Highly efficient electrogenerated chemiluminescence (ECL) of natural chlorophyll a (Chl a) was observed in acetonitrile with 1-butyl-3-methylimidazolium hexafluorophosphate as electrolyte and tri-n-propylamine (TPrA) as a coreactant. The collected ECL spectrum displayed a maximum emission peak at ca. 670 nm, suggesting that the same excited states with the photo-excitation processes were generated. The possible ECL reaction mechanism of this Chl a–TPrA system was discussed and established. ECL intensity of Chl a was proportional to its concentration over the range of 0.1–11 μM, and a high ECL efficiency (Φ_ecl) of 0.86 was calculated using Ru(bpy)₃^2 + as the standard (Φ_ecl = 1). Herein, an important property of natural Chl a was expanded and a new kind of ECL luminophores was developed. Moreover, it is expected that this high ECL efficiency of natural porphyrin complex has great potential to expand its ECL sensing application.     

Thermodynamic studies for aqueous solutions involving 18-crown-6 and alkali bromides at 298.15 K

Osmotic vapor pressure measurements have been carried out for three ternary systems, H₂O + 0.2 m 18-crown-6 + NaBr, H₂O + 0.2 m 18-crown-6 + KBr and H₂O + 0.2 m 18-crown-6 + CsBr at 298.15 K using vapor pressure osmometry. The concentration of salts was varied between 0.04 and 0.6 m. The measured water activities were used to calculate the activity coefficient of water, 18-crown-6 and mean molal activity coefficients of ions. The lowering of activity coefficients of one component in presence of other is attributed to the existence of host–guest type complex equilibria in solution phase. The Gibbs transfer free energies, which have been calculated using the activity data, were used to estimate the McMillan–Mayer pair and triplet interaction parameters and are compared with that of alkali chlorides reported recently by us using similar studies. The pair interaction parameters, g_NE (non-electrolyte–electrolyte interaction coefficient), are used to obtain the thermodynamic equilibrium constant values for 18-crown-6:M⁺ complexes, which on comparison with alkali chlorides indicate that the counter anions plays a definite role in stabilizing such complexes in solution phase. Sign and the magnitude of triplet interaction parameters (g_NNE or g_NEE) show that along with electrostatic interactions hydrophobic effects also play an important role in stabilizing the host–guest type complexes.     

Synthesis,crystal structure,and magnetic properties of a copper(II) octacyanotungstate(V)-based magnet containing two types of organic ligands

Cu₃[W(CN)₈]₂(pyrimidine)₂(3-cyanopyridine)₂ · 4H₂O, a cyanide-bridged copper(II) octacyanotungstate(V) with two types of organic ligands (pyrimidine and 3-cyanopyridine), is prepared. In this compound, the coordination geometry of W is an 8-coordinated bicapped trigonal prism where five CN groups of [W(CN)₈] are bridged to five Cu ions, and the remaining three CN groups are free. The coordination geometries of the three types of Cu ions (Cu1, Cu2, and Cu3) are 6-coordinated pseudo-octahedron. The cyano-bridged-Cu2–W–Cu3-layer is linked by a Cu1 pillar unit, and a cavity along the a axis, which is occupied by 3-cyanopyridine molecules and zeolitic water molecules, exists. The present compound shows ferrimagnetism with a Currie temperature of 7 K, a saturation magnetization of 2.9 μ_B, and a coercive field of 7 Oe at 2 K.     

Spin-crossover in dimeric hydrogen-bonded iron(II) 2-(pyrazolyl)-pyridine and 2-(imidazolyl)-pyridine complexes

Five new hydrogen-bonded solvated iron(II) complexes of pyrazolyl- and imidazolyl-based N,N-chelating ligands have been synthesised. Water to ligand-NH hydrogen-bonded bridges occur in the pseudo-dimeric complexes {cis-[Fe(pypzH)₂(NCX)₂]₂(μ-OH₂)(H₂O)₂} · H₂O · MeOH (where X = S or Se), and in the chain complex {cis-[Fe(pypzH)₂(NCS)₂](μ-OH₂)}_n. A “half” spin-crossover (T_c = 125 K) was observed in the dimeric X = Se complex by means of magnetic measurements and no thermal hysteresis occurred between 4 and 300 K. The crystal structure at 123 K showed Fe–N distances consistent with the magnetism. Each Fe in the dimeric unit was structurally equivalent in the HS–LS state. Removal of the solvate molecules led to HS–HS behaviour over the temperature range 4–300 K. The pseudo-dimer with X = S also showed HS–HS behaviour as did the monomeric analogue cis-[Fe(pypzH)₂(NCS)₂]H₂O and a structurally different methanol-bridged dimer {cis-[Fe(pyimH)₂(NCS)₂]₂(μ-MeOH)₂} · 2MeOH (pypzH = 2-(1H-pyrazol-3-yl)-pyridine; pyimH = 2-(1H-imidazol-2-yl)-pyridine).     

Lead-free solder alloys: Thermodynamic properties of the (Au + Sb + Sn) and the (Au + Sb) system

The thermodynamic properties of liquid (Au–Sb–Sn) alloys were studied with an electromotive force (EMF) method using the eutectic mixture of KCl/LiCl with addition of SnCl₂ as a liquid electrolyte. Activities of Sn in the liquid alloys were measured at three cross-sections with constant molar ratios of Au:Sb = 2:1, 1:1, and 1:2 with tin in the concentration range between 5 at.% and 90 at.% from the liquidus of the samples up to 1073 K. The integral Gibbs excess energies and the integral enthalpies at 873 K were calculated by Gibbs–Duhem integration. Additionally liquid Au–Sb alloys have been measured at 913 K with the EMF method as no reliable data for the Gibbs excess energies have been found in literature. The eutectic mixture of KCl/LiCl with addition of SbCl₃ has been used as an electrolyte for the measurements. The Gibbs excess energies from the (Au + Sb) system were necessary for the integration of the thermodynamic properties of the ternary (Au + Sb + Sn) system.     

Proton-conducting solid oxide fuel cell (SOFC) with Y-doped BaZrO3 electrolyte

Y-doped BaZrO₃ (BZY) electrolyte films are successfully fabricated by utilizing the driving force from the anode substrate, aiming to circumvent the refractory nature of BZY materials. The BZY electrolyte film on the high shrinkage anode becomes dense after sintering even though no sintering aid is added, while the BZY electrolyte remains porous on the conventional anode substrate after the same treatment. The resulting BZY electrolyte shows a high conductivity of 4.5 × 10^− 3 S cm^− 1 at 600 °C, which is 2 to 20 times higher than that for most of BZY electrolyte films in previous reports. In addition, the fuel cell with this BZY electrolyte generates a high power output of 267 mW cm^− 2 at 600 °C. These results suggest the strategy presented in this study provides a promising way to prepare BZY electrolyte films for fuel cell applications.