Sodium-Poor, Hydroxyl-Rich, Defective NaTiO Prepared by γ-Irradiation and Its Enhanced Proton Conductivity.

The use of γ-irradiation to tailor the physicochemical properties of materials is not widely applied to layered alkali metal oxides. Herein, we show that γ-irradiation (up to 400 kGy) of NaTiO leads to a sodium-poor, hydroxyl-rich analogue where the layered structure, plate-like morphology, and textural properties are preserved. The deintercalation of sodium ions modifies the Ti-O bond lengths and expands the unit cell; the latter is supported by density functional theory (DFT) calculations.

Proton Intercalation into an Open-Tunnel Bronze Phase with Near-Zero Volume Change.

Managing safety and supply-chain risks associated with lithium-ion batteries (LIBs) is an urgent task for sustainable development. Aqueous proton batteries are attractive alternatives to LIBs because using water and protons addresses these two risks. However, most host materials undergo large volume changes upon H intercalation, which induces intraparticle cracking to accelerates parasitic reactions.

MgO-Template Synthesis of Extremely High Capacity Hard Carbon for Na-Ion Battery.

Extremely high capacity hard carbon for Na-ion battery, delivering 478 mAh g , is successfully synthesized by heating a freeze-dried mixture of magnesium gluconate and glucose by a MgO-template technique. Influences of synthetic conditions and nano-structures on electrochemical Na storage properties in the hard carbon are systematically studied to maximize the reversible capacity. Nano-sized MgO particles are formed in a carbon matrix prepared by pre-treatment of the mixture at 600 °C.

Crystal structures of four isomeric hydrogen-bonded co-crystals of 6-methyl-quinoline with 2-chloro-4-nitro-benzoic acid, 2-chloro-5-nitro-benzoic acid, 3-chloro-2-nitro-benzoic acid and 4-chloro-2-nitro-benzoic acid.

The structures of the four isomeric compounds of 6-methyl-quinoline with chloro- and nitro-substituted benzoic acids, CHClNO·CHN, namely, 2-chloro-4-nitro-benzoic acid-6-methyl-quinoline (1/1), (I), 2-chloro-5-nitro-benzoic acid-6-methyl-quinoline (1/1), (II), 3-chloro-2-nitro-benzoic acid-6-methyl-quinoline (1/1), (III), and 4-chloro-2-nitro-benzoic acid-6-methyl-quinoline (1/1), (IV), have been determined at 185-190 K. In each compound, the acid and base mol-ecules are linked by a short hydrogen bond between a carboxyl O atom and an N atom of the base. The O⋯N distances are 2.

Reaction Behavior of a Silicide Electrode with Lithium in an Ionic-Liquid Electrolyte.

Silicides are attractive novel active materials for use in the negative-electrodes of next-generation lithium-ion batteries that use certain ionic-liquid electrolytes; however, the reaction mechanism of the above combination is yet to be clarified. Possible reactions at the silicide electrode are as follows: deposition and dissolution of Li metal on the electrode, lithiation and delithiation of Si, which would result from the phase separation of the silicide, and alloying and dealloying of the silicide with Li. Herein, we examined these possibilities using various analysis methods.

Crystal structure of 4-chloro-2-nitro-benzoic acid with 4-hy-droxy-quinoline: a disordered structure over two states of 4-chloro-2-nitro-benzoic acid-quinolin-4(1)-one (1/1) and 4-hy-droxy-quinolinium 4-chloro-2-nitro-benzoate.

The title compound, CHNO·CHClNO, was analysed as a disordered structure over two states, . co-crystal and salt, accompanied by a keto-enol tautomerization in the base mol-ecule. The co-crystal is 4-chloro-2-nitro-benzoic acid-quinolin-4(1)-one (1/1), CHClNO·CHNO, and the salt is 4-hy-droxy-quinolinium 4-chloro-2-nitro-benzoate, CHNO·CHClNO .

Crystal structures of the two isomeric hydrogen-bonded cocrystals 2-chloro-4-nitro-benzoic acid-5-nitro-quinoline (1/1) and 5-chloro-2-nitro-benzoic acid-5-nitro-quinoline (1/1).

The structures of two isomeric com-pounds of 5-nitro-quinoline with chloro- and nitro-substituted benzoic acid, namely, 2-chloro-4-nitro-benzoic acid-5-nitro-quinoline (1/1), (I), and 5-chloro-2-nitro-benzoic acid-5-nitro-quinoline (1/1), (II), both CHClNO·CHNO, have been determined at 190 K. In each com-pound, the acid and base mol-ecules are held together by an O-H⋯N hydrogen bond. In the crystal of (I), the hydrogen-bonded acid-base units are linked by a C-H⋯O hydrogen bond, forming a tape structure along [10].

Crystal structures of 3-chloro-2-nitro-benzoic acid with quinoline derivatives: 3-chloro-2-nitro-benzoic acid-5-nitro-quinoline (1/1), 3-chloro-2-nitro-benzoic acid-6-nitro-quinoline (1/1) and 8-hy-droxy-quinolinium 3-chloro-2-nitro-benzoate.

The structures of three compounds of 3-chloro-2-nitro-benzoic acid with 5-nitro-quinoline, (I), 6-nitro-quinoline, (II), and 8-hy-droxy-quinoline, (III), have been determined at 190 K. In each of the two isomeric compounds, (I) and (II), CHClNO·CHNO, the acid and base mol-ecules are held together by O-H⋯N and C-H⋯O hydrogen bonds. In compound (III), CHNO·CHClNO , an acid-base inter-action involving H-atom transfer occurs and the H atom is located at the N site of the base mol-ecule.

Negative dielectric constant of water confined in nanosheets.

Electric double-layer capacitors are efficient energy storage devices that have the potential to account for uneven power demand in sustainable energy systems. Earlier attempts to improve an unsatisfactory capacitance of electric double-layer capacitors have focused on meso- or nanostructuring to increase the accessible surface area and minimize the distance between the adsorbed ions and the electrode. However, the dielectric constant of the electrolyte solvent embedded between adsorbed ions and the electrode surface, which also governs the capacitance, has not been previously exploited to manipulate the capacitance.

Crystal structures of two hydrogen-bonded compounds of chloranilic acid-ethyl-eneurea (1/1) and chloranilic acid-hydantoin (1/2).

The structures of the hydrogen-bonded 1:1 co-crystal of chloranilic acid (systematic name: 2,5-di-chloro-3,6-dihy-droxy-1,4-benzo-quinone) with ethyl-eneurea (systematic name: imidazolidin-2-one), CHClO·CHNO, (I), and the 1:2 co-crystal of chloranilic acid with hydantoin (systematic name: imidazolidine-2,4-dione), CHClO·2CHNO, (II), have been determined at 180 K. In the crystals of both compounds, the base mol-ecules are in the lactam form and no acid-base inter-action involving H-atom transfer is observed. The asymmetric unit of (I) consists of two independent half-mol-ecules of chloranilic acid, with each of the acid mol-ecules lying about an inversion centre, and one ethyl-eneurea mol-ecule.

Surface modification effects on the tensile properties of functionalised graphene oxide epoxy films.

Graphene oxide (GO) is a candidate for nanofillers to improve the mechanical and thermal stability of nanocomposites. In order to determine the molecular interaction to improve the mechanical properties of GO-epoxy resin composites, we investigated the relationship between GO oxidation properties and the tensile strength of the epoxy resin. With respect to GO preparation, graphite was oxidised by the Brodie or Hummers method, and the oxidised GO was reduced or chloride substituted.

Crystal structures of two 1:2 dihydrate compounds of chloranilic acid with 2-carb-oxy-pyridine and 2-carb-oxy-quinoline.

The crystal structure of the 1:2 dihydrate compound of chloranilic acid (systematic name: 2,5-di-chloro-3,6-dihy-droxy-1,4-benzo-quinone) with 2-carb-oxy-pyridine (another common name: picolinic acid; systematic name: pyridine-2-carb-oxy-lic acid), namely, 2CHNO·CHClO·2HO, (I), has been determined at 180 K, and the structure of the 1:2 dihydrate compound of chloranilic acid with 2-carb-oxy-quinoline (another common name: quinaldic acid; systematic name: quinoline-2-carb-oxy-lic acid), namely, 2CHNO·CHClO·2HO, (II), has been redetermined at 200 K. This determination presents a higher precision crystal structure than the previously published structure [Marfo-Owusu & Thompson (2014 ▸). , , 55-56].

Crystal structures of three hydrogen-bonded 1:2 compounds of chloranilic acid with 2-pyridone, 3-hy-droxy-pyridine and 4-hyroxypyridine.

The crystal structures of the 1:2 compounds of chloranilic acid (systematic name: 2,5-di-chloro-3,6-dihy-droxy-1,4-benzo-quinone) with 2-pyridone, 3-hy-droxy-pyridine and 4-hyroxypyridine, namely, bis-(2-pyridone) chloranilic acid, 2CHNO·CHClO, (I), bis-(3-hy-droxy-pyridinium) chloranilate, 2CHNO·CClO, (II), and bis-(4-hy-droxy-pyridinium) chloranilate, 2CHNO·CClO, (III), have been determined at 120 K. In the crystal of (I), the base mol-ecule is in the lactam form and no acid-base inter-action involving H-atom transfer is observed. The acid mol-ecule lies on an inversion centre and the asymmetric unit consists of one half-mol-ecule of chloranilic acid and one 2-pyridone mol-ecule, which are linked a short O-H⋯O hydrogen bond.

Crystal structures of 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1) and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2).

The crystal structures of two hydrogen-bonded compounds, namely 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1), CHN·CHO·CHO, (I), and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2), CHO·CHNO·CHNO, (II), have been determined at 93 K. In (I), the asymmetric unit consists of two crystallographically independent 4-meth-oxy-benzoic acid mol-ecules and one 1,3-bis-(pyridin-4-yl)propane mol-ecule. The asymmetric unit of (II) comprises one biphenyl-4,4'-di-carb-oxy-lic acid mol-ecule and two independent 4-meth-oxy-pyridine mol-ecules.

Crystal structures of hydrogen-bonded co-crystals as liquid crystal precursors: 4-(-pent-yloxy)benzoic acid-()-1,2-bis-(pyridin-4-yl)ethene (2/1) and 4-(-hex-yloxy)benzoic acid-()-1,2-bis-(pyridin-4-yl)ethene (2/1).

The crystal structures of title hydrogen-bonded co-crystals, 2CHO·CHN, (I), and 2CHO·CHN, (II), have been determined at 93 K. In (I), the asymmetric unit consists of one 4-(-pent-yloxy)benzoic acid mol-ecule and one half-mol-ecule of ()-1,2-bis-(pyridin-4-yl)ethene, which lies about an inversion centre. The asymmetric unit of (II) comprises two crystallographically independent 4-(-hex-yloxy)benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethene mol-ecule.

Crystal structures of four co-crystals of ()-1,2-di(pyridin-4-yl)ethene with 4-alk-oxy-benzoic acids: 4-meth-oxy-benzoic acid-()-1,2-di(pyridin-4-yl)ethene (2/1), 4-eth-oxy-benzoic acid-()-1,2-di(pyridin-4-yl)ethene (2/1), 4--propoxybenzoic acid-()-1,2-di(pyridin-4-yl)ethene (2/1) and 4--but-oxy-benzoic acid-()-1,2-di(pyridin-4-yl)ethene (2/1).

The crystal structures of four hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-()-1,2-di(pyridin-4-yl)ethene (2/1), namely, 2CHO·CHN, (I), 2CHO·CHN, (II), 2CHO·CHN, (III) and 2CHO·CHN, (IV), have been determined at 93 K. In compounds (I) and (IV), the asymmetric units are each composed of one 4-alk-oxy-benzoic acid mol-ecule and one half-mol-ecule of ()-1,2-di(pyridin-4-yl)ethene, which lies on an inversion centre. The asymmetric unit of (II) consists of two crystallographically independent 4-eth-oxy-benzoic acid mol-ecules and one 1,2-di(pyridin-4-yl)ethene mol-ecule.

Sodium-Ion Intercalation Mechanism in MXene Nanosheets.

MXene, a family of layered compounds consisting of nanosheets, is emerging as an electrode material for various electrochemical energy storage devices including supercapacitors, lithium-ion batteries, and sodium-ion batteries. However, the mechanism of its electrochemical reaction is not yet fully understood. Herein, using solid-state (23)Na magic angle spinning NMR and density functional theory calculation, we reveal that MXene Ti3C2Tx in a nonaqueous Na(+) electrolyte exhibits reversible Na(+) intercalation/deintercalation into the interlayer space.

Crystal structures of three co-crystals of 1,2-bis-(pyridin-4-yl)ethane with 4-alk-oxy-benzoic acids: 4-eth-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), 4-n-propoxybenzoic acid-1,2-bis(pyridin-4-yl)ethane (2/1) and 4-n-but-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1).

The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), namely, 2C9H10O3·C12H12N2, (I), 2C10H12O3·C12H12N2, (II), and 2C11H14O3·C12H12N2, (III), have been determined at 93, 290 and 93 K, respectively. In (I), the asymmetric unit consists of one 4-eth-oxy-benzoic acid mol-ecule and one half-mol-ecule of 1,2-bis-(pyridin-4-yl)ethane, which lies on an inversion centre. In (II) and (III), the asymmetric units each comprise two crystallographically independent 4-alk-oxy-benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethane mol-ecule.

Crystal structures of three co-crystals of 4,4'-bipyridyl with 4-alk-oxy-benzoic acids: 4-eth-oxy-benzoic acid-4,4'-bipyridyl (2/1), 4-n-propoxybenzoic acid-4,4'-bipyridyl (2/1) and 4-n-but-oxy-benzoic acid-4,4'-bipyridyl (2/1).

The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-4,4'-bipyridyl (2/1), namely, 2C9H10O3·C10H8N2, (I), 2C10H12O3·C10H8N2, (II) and 2C11H14O3·C10H8N2, (III), have been determined at 93 K. Although the structure of (I) has been determined in the space group P21 with Z = 4 [Lai et al. (2008 ▸).

Crystal structures of morpholinium hydrogen bromanilate at 130, 145 and 180 K.

Crystal structures of the title compound (systematic name: morpholin-4-ium 2,5-di-bromo-4-hy-droxy-3,6-dioxo-cyclo-hexa-1,4-dien-1-olate), C4H10NO(+)·C6HBr2O4 (-), were determined at three temperatures, viz. 130, 145 and 180 K. The asymmetric unit comprises one morpholinium cation and two halves of crystallographically independent bromanilate monoanions, which are located on inversion centres.

Crystal structures of iso-quinoline-3-chloro-2-nitro-benzoic acid (1/1) and isoquinolinium 4-chloro-2-nitro-benzoate.

In each of the title isomeric compounds, C9H7.3N·C7H3.7ClNO4, (I), and C9H8N·C7H3ClNO4, (II), of iso-quinoline with 3-chloro-2-nitro-benzoic acid and 4-chloro-2-nitro-benzoic acid, the two components are linked by a short hydrogen bond between a base N atom and a carb-oxy O atom.

An extended phenacene-type molecule, [8]phenacene: synthesis and transistor application.

A new phenacene-type molecule, [8]phenacene, which is an extended zigzag chain of coplanar fused benzene rings, has been synthesised for use in an organic field-effect transistor (FET). The molecule consists of a phenacene core of eight benzene rings, which has a lengthy π-conjugated system. The structure was verified by elemental analysis, solid-state NMR, X-ray diffraction (XRD) pattern, absorption spectrum and photoelectron yield spectroscopy (PYS).

Bis(4-meth-oxy-3,4-di-hydro-quinazolin-1-ium) chloranilate.

IN THE TITLE COMPOUND [SYSTEMATIC NAME: bis-(4-meth-oxy-3,4-di-hydro-quinazolin-1-ium) 2,5-di-chloro-3,6-dioxo-cyclo-hexa-1,4-diene-1,4-diolate], 2C9H11N2O(+)·C6Cl2O4 (2-), the chloranil-ate anion lies about an inversion center. The 4-meth-oxy-3,4-di-hydro-quinazolin-1-ium cations are linked on both sides of the anion via bifurcated N-H⋯(O,O) and weak C-H⋯O hydrogen bonds, giving a centrosymmetric 2:1 aggregate. The 2:1 aggregates are linked by another N-H⋯O hydrogen bond into a tape running along [1-10].

Bis(tri-ethyl-ammonium) chloranilate.

IN THE CRYSTAL STRUCTURE OF THE TITLE COMPOUND [SYSTEMATIC NAME: bis-(tri-ethyl-ammonium) 2,5-di-chloro-3,6-dioxo-cyclo-hexa-1,4-diene-1,4-diolate], 2C6H16N(+)·C6Cl2O4 (2-), the chloranilate anion lies on an inversion center. The tri-ethyl-ammonium cations are linked on both sides of the anion via bifurcated N-H⋯(O,O) and weak C-H⋯O hydrogen bonds to give a centrosymmetric 2:1 aggregate. The 2:1 aggregates are further linked by C-H⋯O hydrogen bonds into a zigzag chain running along [01-1].

A triclinic polymorph of 4-cyano-pyridinium hydrogen chloranilate.

THE ASYMMETRIC UNIT OF THE TRICLINIC POLYMORPH OF THE TITLE COMPOUND (SYSTEMATIC NAME: 4-cyano-pyridinium 2,5-dichloro-4-hy-droxy-3,6-dioxocyclo-hexa-1,4-dien-1-olate), C(6)H(5)N(2) (+)·C(6)HCl(2)O(4) (-), consists of two crystallographically independent cation-anion units, in each of which the cation and the anion are linked by an N-H⋯O hydrogen bond. In the units, the dihedral angles between the cation and anion rings are 78.43 (11) and 80.