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CO2 hydrogenation to methanol has been extensively studied over Cu-based catalysts. H2O is an inevitable by-product during this reaction process. The essential role of H2O in determining the catalytic performance remains controversial. Herein, three kinds of common Cu-based catalysts (Cu/ZnO, Cu/Al2O3, Cu/SiO2) were selected to investigate the effect of H2O on the reaction performance over the range of 190 °C–290 °C in detail. Of all catalysts tested, it was noted that adding H2O showed substantially different effects on the methanol selectivity compared with the normal reaction. The representative Cu/SiO2 catalyst was further selected to investigate the role of H2O through a series of characterizations including BET, XRD, TEM, H2-TPR and XPS, etc. Moreover, in situ FT-IR experiment was further conducted to understand the effect of H2O on the reaction pathways. The results indicated that H2O played the significant role on regulating the methanol selectivity by inhibiting and promoting the transformation from monodentate carbonate to bidentate formate over all the Cu-based catalysts at low (190–230 °C) and high (230–290 °C) temperature ranges, respectively. This preliminary study offers directions for the optimization of experimental conditions for the H2O involving reactions and provides referable experience for the further exploration and utilization of H2O effects on related fields as well. The addition of H2O shows a significant characteristic effect on methanol selectivity by inhibiting and promoting the conversion of monodentate carbonate to bidentate formate at low (190–230 ℃) and high (230–290 ℃) temperatures ranges, respectively. [ABSTRACT FROM AUTHOR]

Adopting a solvothermal method, a new Zn‐MOF (metal‐organic framework, MOF), namely, [Zn5(FA)4(LBTX)(OH)2]n (1) has been successfully synthesized (H2FA=2,2‐bis(4‐carboxyphenyl)hexafluoropropylene, LBTX=4,4'‐bis(1H‐1,2,4‐triazole‐1‐yl)methyl‐1,1'‐biphenyl). Complex 1 was structurally characterized by single‐crystal X‐ray diffraction analysis, powder X‐ray diffraction (PXRD), thermogravimetric analyses (TGA), infrared spectra (IR) and elemental analyses (EA). X‐ray diffraction analysis revealed that complex 1 features a two‐fold interpenetrated pcu‐topological architecture. Complex 1 has a multi‐response photoluminescence sensing feature that it can be used to detect Fe3+, CrO42−, Cr2O72−, MnO4− ions in water. The possible quenching mechanism were also explored. [ABSTRACT FROM AUTHOR]

Although reducing graphene oxide (GO) is a promising method for producing graphene, it involves high energy consumption and serious pollution. Here, an eco-friendly and cost-effective method to reduce GO was developed, in which GO was reduced by a fermentation-medium system containing self-secreted [FeFe]-hydrogenase (CFM-H 2 ase). It was found that GO could be rapidly reduced by hydrogen which was catalyzed by the fermentation medium of Escherichia coli that heterologously expressed [FeFe] hydrogenase. The reduced GO nanosheets were characterized and confirmed by Raman, XRD, and XPS analysis, which indicated a high reduction ratio was achieved. Further analysis revealed that the [FeFe] hydrogenase secreted by the genetically engineered E. coli cells was responsible for the catalysis of hydrogen-induced GO reduction, which was the underlying mechanism for GO reduction by the CFM-H 2 ase system. This work demonstrated a new enzymatic approach for GO reduction, which would be helpful in developing a more sustainable graphene industry. [Display omitted] • A new approach for green preparation of graphene was developed. • Fermentation medium with hydrogenase was applied for graphene oxide reduction. • Self-secreted hydrogenase played key role on graphene oxide bioreduction. • This cell-free approach was superior to cell-based preparation of graphene. [ABSTRACT FROM AUTHOR]

We have systematically investigated the crystal structure of Ba-doped phenanthrene with various Ba doping levels by the first-principles calculations combined with the X-ray diffraction (XRD) spectra simulations. Although the experimental stoichiometry ratio of Ba atom and phenanthrene molecule is 1.5:1, the simulated XRD spectra, space group symmetry and optimized lattice parameters of Ba15phenanthrene are not consistent with the experimental ones, while the results for Ba2phenanthrene are in good agreement with the measurements. The strength difference of a few XRD peaks can be explained by the existence of pristine phenanthrene. Our findings suggest that instead of uniform Ba15phenanthrene, there coexist Ba2phenanthrene and undoped phenanthrene in the superconducting sample. The electronic calculations indicate that Ba2phenanthrene is a semiconductor with a small energy gap less than 0.05 eV. [ABSTRACT FROM AUTHOR]

This paper has studied the crystal structure, growth orientation, crystal quality and thermionic emission properties of the La 0.9 Sr 0.1 B 6 single crystal prepared by the optical floating zone method. By the means of XRD, single crystal X-ray diffraction, X-ray Laue diffraction, X-ray rocking curve and TEM, the La 0.9 Sr 0.1 B 6 single crystal grown along [100] orientation is determined to be a single-phase solid solution of Sr-doped LaB 6 with the typical cubic structure and have a good crystal quality and integrity. The higher J 1kV (42.55 A/cm2), J o (31.19 A/cm2) and lower Φ eff (2.492 eV) than LaB 6 under the cathode operating temperature of 1500 °C as well as the good thermionic emission stability strongly suggest that the grown La 0.9 Sr 0.1 B 6 single crystal has a good potential to be a promising hot cathode material. • The high-quality [100] La 0.9 Sr 0.1 B 6 single crystal is prepared by the OFZM. • The grown single crystal is a single-phase solid solution of Sr-doped LaB 6. • The current density of La 0.9 Sr 0.1 B 6 single crystal is higher than that of LaB 6. • The La 0.9 Sr 0.1 B 6 single crystal has the good thermionic emission stability. [ABSTRACT FROM AUTHOR]

Photosynthesis plays a vital role on earth and photo-induced organic reactions have artificially created many valuable materials. However, the photo-induced syntheses of inorganic compounds are much less reported. Herein, we report the photo-assisted synthesis of a mixed-valence polyoxovanadate with the formula [C9H14N]6[V15O36Cl], under AM1.5 irradiation in a N2 atmosphere. Single-crystal X-ray diffraction analysis reveals a hexagonal structure (space group P63/mmc) with cell parameters: a = 14.1100(6) Å, b = 14.1100(6) Å, c = 22.0265(10) Å, and V = 3797.8(4) Å3. UV-Vis and EPR analyses verified that the [V15O36Cl]6− cluster formed within 0.5 h; powder XRD results indicated that the crystalline phase appeared after irradiation for 9.5 h (200 mW cm−2). These findings suggested that the nucleation and crystallization processes took longer than [V15O36Cl]6− cluster formation and dominated the [C9H14N]6[V15O36Cl] crystal formation. This primary work could open the door for the syntheses of inorganic compounds using photo-assisted reactions instead of conventional thermo-driving syntheses. [ABSTRACT FROM AUTHOR]

Over the last decade, Na‐ion batteries have been extensively studied as low‐cost alternatives to Li‐ion batteries for large‐scale grid storage applications; however, the development of high‐energy positive electrodes remains a major challenge. Materials with a polyanionic framework, such as Na superionic conductor (NASICON)‐structured cathodes with formula NaxM2(PO4)3, have attracted considerable attention because of their stable 3D crystal structure and high operating potential. Herein, a novel NASICON‐type compound, Na4MnCr(PO4)3, is reported as a promising cathode material for Na‐ion batteries that deliver a high specific capacity of 130 mAh g−1 during discharge utilizing high‐voltage Mn2+/3+ (3.5 V), Mn3+/4+ (4.0 V), and Cr3+/4+ (4.35 V) transition metal redox. In addition, Na4MnCr(PO4)3 exhibits a high rate capability (97 mAh g−1 at 5 C) and excellent all‐temperature performance. In situ X‐ray diffraction and synchrotron X‐ray diffraction analyses reveal reversible structural evolution for both charge and discharge. [ABSTRACT FROM AUTHOR]

A synchrotron‐based scanning X‐ray diffraction study on a GaP/Si pseudo‐substrate is reported, within the context of the monolithic integration of photonics on silicon. Two‐dimensional real‐space mappings of local lattice tilt and in‐plane strain from the scattering spot distributions are measured on a 200 nm partially relaxed GaP layer grown epitaxially on an Si(001) substrate, using an advanced sub‐micrometre X‐ray diffraction microscopy technique (K‐Map). Cross‐hatch‐like patterns are observed in both the local tilt mappings and the in‐plane strain mappings. The origin of the in‐plane local strain variation is proposed to be a result of misfit dislocations, according to a comparison between in‐plane strain mappings and transmission electron microscopy observations. Finally, the relationship between the in‐plane strain and the free surface roughness is also discussed using a statistical method. [ABSTRACT FROM AUTHOR]

• A dual-cycle regeneration method of Fe-NH 2 -PAN adsorbent was established. • Coordination and electrostatic attraction were the adsorption mechanisms. • High-purity FePO 4 was achieved from the desorption solution at pH -1.6. • LiFePO 4 /C electrodes made of recycled FePO 4 exhibited a better discharge capacity. The recovery of high-purity and high-value FePO 4 raw materials from wastewater has great prospects in LiFePO 4 battery industry due to the huge demand for new energy vehicle. However, the conventional in-situ FePO 4 precipitation, as well as ex-situ PO 4 3− adsorption-alkali regeneration, was incapable of efficiently obtaining high-purity products. To solve these problems, a dual-cycle regeneration method of Fe-NH 2 -polyacrylonitrile (PAN) adsorbent and H 2 SO 4 desorbing solution was proposed to ex-situ FePO 4 recovery from wastewater for Li-battery application. Benefitted from coordination interaction and electrostatic attraction, the maximum PO 4 3− adsorption capacity of Fe-NH 2 -PAN reached 73.1 ± 0.4 mg/g. The average PO 4 3− removal rate of continuous flow devices were 88.5% and 91.3% when treating low-P-concentration (0.22 mg/L) municipal wastewater (MW) and high-P-concentration (48.9 mg/L) slaughterhouse wastewater (SW) respectively. Furthermore, high-purity FePO 4 analyzed by XRD spectra was achieved from the desorption solution at pH ∼1.6, resulting in the ultrahigh P recovery efficiencies of 91.4 ± 3.2%−96.3 ± 2.5% for SW and 82.7 ± 3.5% for MW. Besides, the LiFePO 4 /C electrodes made of recycled FePO 4 exhibited a better discharge capacity (37.3 − 55.8 mAh/g) than that of commercial FePO 4 agent (32.2 − 35.1 mAh/g) from 80 to 132 cycles, which showed the promising feasibility of recovering FePO 4 from wastewater for Li-battery application. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Mechanical fatigue behavior of AL6XN stainless steel as a typical type of planar slip alloy was investigated by in situ neutron diffraction and synchrotron-based X-ray microdiffraction methods. Under cyclic loading at a high strain amplitude (±0.8%), the fatigue damage originated mainly from the accumulation of statistical stored dislocations, as clearly evidenced from a continuous increase in diffraction peak width with increasing the number of load cycles. However, under cyclic loading at a low strain amplitude (±0.3%), the density of statistical stored dislocations became saturated just after a hundred loading cycles and the fatigue damage was mainly dominated by the accumulation of persistent Lüders bands (PLBs) and the complex interactions among various PLBs as evidenced through X-ray microdiffraction measurements. It was further found that there exists obvious grain-orientation-dependent local damage in the low-strain-amplitude fatigued sample. In particular, fatigued grains orientated with [001] paralleling the loading direction are subjected to compressive stress and contain a large number of broad PLBs in boundaries arraying the edge dislocation pile-ups, which generate a large stress gradient leading to local plastic instability. The highly localized stress field at PLBs in the cyclically-deformed sample at a low strain amplitude may explain the obvious cyclic stress softening. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract The high-quality La x Ce y Pr 1-x-y B 6 (x = 0.6–0.8, y = 0.1–0.3) single crystals have been firstly grown by optical floating zone melting method. The crystal structure, mechanical and thermionic emission properties of the as-grown single crystals were characterized by X-ray single crystal diffractometer, SEM, XRD, X-ray Laue diffraction. Subgrain-boundary-free [100] La x Ce y Pr 1-x-y B 6 single crystal with a good crystalline integrity and homogeneous element distribution is obtained. The Lattice constant of La x Ce y Pr 1-x-y B 6 single crystal is lower than that of the LaB 6 single crystal. The lowest FWHM of 162.0 arcsec belongs to the La 0.6 Ce 0.3 Pr 0.1 B 6 single crystal. The highest thermionic emission current density of 105.10 A/cm2 and the lowest work function of 2.562 eV indicate that La 0.6 Ce 0.3 Pr 0.1 B 6 single crystal is a very promising thermionic cathode material. Highlights • High-quality La x Ce y Pr 1-x-y B 6 single crystal is firstly grown. • The current density of single crystal is inversely proportional to the FWHM. • The current density of La x Ce y Pr 1-x-y B 6 single crystal is higher than that of LaB 6. [ABSTRACT FROM AUTHOR]

Abstract The present work showed the biofabrication and characterization of gold nanoparticles (Au NPs) using Coccinia grandis bark extract. The fabricated NPs were well characterized by using different microscopic an spectroscopic techniques such as transmission electron microscopy (TEM), Ultra violet – visible spectroscopy (UV–Vis), X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS) and Fourier transform spectroscopy (FTIR). TEM results showed that the prepared AuNPs are spherical in shape with uniformity in size. The calculated average size of the AuNPs is 20 nm. The NAC drug molecule that is used for cataract treatment was successfully encapsulated into Au NPs to increase its bioavailability. Also, the in-vitro cytotoxicity of NAC and NAC - Au NPs were studied against fibroblast cells, and the results showed that encapsulation of NAC into Au NPs did not showed cytotoxicity after encapsulation. NAC molecules do not exhibit toxicity at lower concentrations, While, there is a reduction in the number of viable cells at higher concentration of NAC. Also, the encapsulation of the drug onto Au NPs is considerably increased biocompatibility and bioavailability. In future, this research results may be helpful for the development of drugs for treatment of cataract with high stability and reactivity. Graphical abstract Unlabelled Image Highlights • Biofabrication Au NPs using Coccinia grandis bark extract. • Encapsulation of NAC onto Au NPs. • Cytotoxicity of NAC and NAC - Au NPs against fibroblast cells. • Biocompatibility and bioavailability of NAC from NAC-AuNPs. [ABSTRACT FROM AUTHOR]

Oxidation removal process of elemental mercury (Hg 0 ) from flue gas using heat and Co 2+ /Fe 2+ coactivated Oxone oxidation system in a spraying reactor was developed. The effects of several influencing factors and main flue gas compositions on Hg 0 removal, and the active species, products, mechanism and mass transfer-reaction kinetic law of Hg 0 removal process were investigated. The results show that heat and Co 2+ /Fe 2+ have a significant synergistic effect for activating Oxone to produce free radicals and promote Hg 0 removal. Hg 0 removal can be improved via increasing Oxone concentration, Co 2+ /Fe 2+ concentration, activation temperature or O 2 concentration, and is inhibited with increasing solution pH, Hg 0 inlet concentration or NO concentration. Changing SO 2 concentration have double impacts on Hg 0 removal. SO 4 − and OH produced from coactivation of heat and Co 2+ /Fe 2+ are the key oxidants, which play a leading role in Hg 0 removal. Oxone plays a complementary role in Hg 0 removal. Hg 0 removal processes using heat/Co 2+ and heat/Fe 2+ coactivated Oxone systems belong to fast reactions under optimized experimental conditions, and meets a total 2.8-order reaction (i.e. 1.0-order for Hg 0 , 1.1-order for Oxone and 0.7-order for Co 2+ ) in Co 2+ /Oxone activation system, and a total 3.0-order reaction (i.e. 1.0-order for Hg 0 , 1.4-order for Oxone and 0.6-order for Fe 2+ ) in Fe 2+ /Oxone activation system. Finally, the key mass transfer and kinetic parameters of Hg 0 removal processes were also determined. [ABSTRACT FROM AUTHOR]

N-doped porous carbon prepared by high-temperature annealing method was developed as the catalyst for significantly enhancing direct decomposition of NO, the efficiency was up to 93% at 500 °C. In addition, the presence of pyridinic N in the N-doped porous carbon was firstly confirmed as the activated site, thus promoting the performance. [ABSTRACT FROM AUTHOR]

Yb/Ho: CaLaGa 3 O 7 as mid-IR laser crystal was successfully grown by the Czochralski method for the first time. The effects of Yb 3+ on the structure parameters and spectroscopic properties have been investigated. In comparison with Ho 3+ singly-doped CaLaGa 3 O 7 crystal, Yb 3+ not only enhances 2.86 µm emission but also depopulates the Ho 3+ : 5 I 7 level in Yb/Ho: CaLaGa 3 O 7 crystal, which is beneficial to the possible population inversion for Ho 3+ : 5 I 6 → 5 I 7 . Results indicate that the prepared Yb/Ho: CaLaGa 3 O 7 crystal is a promising candidate for 2.86 μm mid-infrared laser applications. [ABSTRACT FROM AUTHOR]

Under the hydrothermal conditions, the simple self-assembly between Cd2+, 2,3,5,6-pyridinetetracarboxylic acid (L1′), and N2H4 created a L12−-based Cd2+ coordination polymer [Cd(L1)(N2H4)] · 2H2O (L12− = 2,3,5,6-pyridinetetracarboxylhydrazidate) 1. H2L1 derived from the in situ acylation of L1′ with N2H4. X-ray single-crystal diffraction analysis reveals that 1 possesses a 1-D chained structure co-bridged by L12− and N2H4, where a castellated CdO single-chain is observed. It is noteworthy that between the L12− molecules, two types of cyclic hydrogen-bonded synthons are found. Via these weak intermolecular interactions, 1 self-assembles into a 3-D porous supramolecular network (window size: 8 × 7 Å2). The tetrahenuclear water clusters with a tetrahedral structure are observed in the pores. [ABSTRACT FROM AUTHOR]

In this work, hierarchical ZnFe 2 O 4 @RGO@CuS composite was synthesized by a simple two-step hydrothermal route, and its constitution, microstructures and microwave absorption properties were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and vector network analyzer (VNA). Experimental results show that hierarchical ZnFe 2 O 4 @RGO@CuS composite exhibits an enhanced electromagnetic wave attenuation capacity, which is ascribed to the suitable impedance match, magnetic loss, dielectric loss and special hierarchical nanostructure. Importantly, the three-dimensional flower-like structure of CuS can produce more multiple reflection and scattering, leading to more consumption of electromagnetic wave energy. The maximum reflection loss of ZnFe 2 O 4 @RGO @CuS composite reaches −55.4 dB at 14.6 GHz and the effective absorption bandwidth (<−10 dB) is as wide as 7.5 GHz (from 10.5 to 18 GHz) for a thickness of only 2.2 mm. Hence, the as-prepared nanocomposite with strong absorption and wide frequency can be a promising absorber in decreasing EM wave interference. [ABSTRACT FROM AUTHOR]

Ferrous(II) phosphate nanoflowers (Fe 3 (PO 4 ) 2 ·8H 2 O NFs) were synthesized by a facial co-precipitation method. The structure, composition and morphology were characterized by XRD, EDX, element mapping and FESEM. The as-prepared Fe 3 (PO 4 ) 2 ·8H 2 O NFs exhibited excellent intrinsic peroxidase-like activity. Steady-state kinetic studies showed that Fe 3 (PO 4 ) 2 ·8H 2 O NFs exhibited stronger affinities with 3,3,5,5-tetramethylbenzidine (TMB) and H 2 O 2 as the substrates compared with the natural horseradish peroxidase (HRP) and the catalytic constant ( k cat ) value was even higher than HRP and other reported nanomaterial based peroxidase mimics. The investigation of the catalytic mechanism by cyclic voltammetry, fluorescence spectroscopy and ESR displayed the catalytic activity of Fe 3 (PO 4 ) 2 ·8H 2 O NFs originated from the generation of •OH. The Fe 3 (PO 4 ) 2 ·8H 2 O NFs also exhibited higher robustness and better storage stability than HRP. Then, a Fe 3 (PO 4 ) 2 ·8H 2 O NFs-based colorimetric platform was developed to determine H 2 O 2 and glucose. The linear range of H 2 O 2 and glucose was as broad as 1 × 10 −5 –2.5 mM and 8 × 10 −4 –1.2 mM, and the detection limit (LOD) was as low as 5 nM and 35 nM, respectively. This simple assay offered a highly sensitive and specific strategy for H 2 O 2 and glucose determination, which had been successfully utilized for real sample analysis with good reproducibility and accuracy. [ABSTRACT FROM AUTHOR]

Four Cd/Zn coordination frameworks, namely, [Cd(TPBA-4)(NO 3 ) 2 ]·2DMF·1.22H 2 O ( 1 ), [Cd(TPBA-4)(NO 3 ) 2 ]·H 2 O ( 2 ), [Cd(TPBA-4)(NO 3 ) 2 ]·2.2Me 2 CO·0.32H 2 O ( 3 ), and [Zn(TPBA-4)(NO 3 ) 2 ]·1.5Me 2 CO ( 4 ) were synthesized by the reaction of N′,N″,N‴-tris(pyrid-4-ylmethyl)-1,3,5-benzenetricarboxamide (TPBA-4) with the corresponding d 10 metal salts. X-ray diffraction analysis revealed that complex 1 was of two-fold interpenetrated 2D network with interlocked cage-like motif. The structure of 2 is three-fold interpenetrated 2D honeycomb network. On the other hand, the 3 and 4 are isomorphous and isostructural, and have different 2D networks compared to 1 and 2 . Thus the series of complexes have the same metal atoms and ligands but different structures. In complex 1 , 2 , 3 , and 4 , the flexible TPBA-4 ligands are versatile and adopt different conformations according to different reaction conditions, which predominates the final structures of these complexes. The physical properties of these complexes were also investigated. [ABSTRACT FROM AUTHOR]

Combined effects of shear flow and non-isothermal processing, which were akin to the practical industrial processing, on the crystallization of metallocene-made isotactic polypropylene (m- i PP) were investigated by in-situ synchrotron wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) techniques. The simultaneous appearance of α - and γ -crystals was observed in quiescent samples, while shear flow led to the occurrence of α -crystals prior to γ -crystals at the initial stage of crystallization. Although the local alignment of chain segments promoted by shear flow facilitated the α -crystals, the relaxation of oriented chains was experimentally confirmed to boost the formation of γ -crystals. Interestingly, the resultant γ -crystal content was higher in the sheared samples than the quiescent counterparts at a given cooling rate and further increased with the decrease of cooling rates. Such a discrepancy was not only related to shear-induced orientation and relaxation, but also was accredited to the advanced crystallization temperature window, which was favorable for the γ -crystal growth. It was quite different from the isothermal crystallization situation, where the formation of γ -crystals was depressed in presence of shear flow. The dynamic competition between α -crystal and γ -crystal formation under the effects of shear during the non-isothermal crystallization was discussed. Our work is of valuable reference to tailor the crystalline structure of m- i PP during practical processing and hence to acquire the desired performance of products. [ABSTRACT FROM AUTHOR]

Inorganic binder-based stabilization/solidification (S/S) of Pb-contaminated soil is a commonly used remediation approach. This paper investigates the influences of soluble Pb species on the hydration process of two types of inorganic binders: ordinary Portland cement (OPC) and magnesium potassium phosphate cement (MKPC). The environmental leachability, compressive strength, and setting time of the cement products are assessed as the primary performance indicators. The mechanisms of Pb involved in the hydration process are analyzed through X-ray diffraction (XRD), hydration heat evolution, and thermogravimetric analyses. Results show that the presence of Pb imposes adverse impact on the compressive strength (decreased by 30.4%) and the final setting time (prolonged by 334.7%) of OPC, but it exerts much less influence on those of MKPC. The reduced strength and delayed setting are attributed to the retarded hydration reaction rate of OPC during the induction period. These results suggest that the OPC-based S/S of soluble Pb mainly depends on physical encapsulation by calcium-silicate-hydrate (C S H) gels. In contrast, in case of MKPC-based S/S process, chemical stabilization with residual phosphate (pyromorphite and lead phosphate precipitation) and physical fixation of cementitious struvite-K are the major mechanisms. Therefore, MKPC is a more efficient and chemically stable inorganic binder for the Pb S/S process. [ABSTRACT FROM AUTHOR]

Crystalline tantalum-containing oxides are usually taken as the advanced photocatalysts for water splitting. How about the amorphous counterparts? In this work, a transformation of crystalline Na 2 Ta 2 O 6 (C Na 2 Ta 2 O 6 ) to amorphous TaO x (Am-TaO x ) was achieved by a facial hydrothermal method. We proposed a transformation mechanism based on nucleation-dissolution -recrystallization and further intensified the influence of base concentration on the composition, crystallinity, and morphology (CCM) as confirmed by XRD, TEM, EDS. N 2 -physisorption, Raman, IR, and XPS analysis. It is found that when comparing to the crystalline counterparts, amorphous samples possessed higher surface area, abundant surface hydration layers and H + adsorption, showing an unassisted photocatalytic water splitting with a rate of 70 ± 7 μmol g −1 h −1 , much larger than that of 15 ± 1 μmol g −1 h −1 of C Na 2 Ta 2 O 6 , 11 ± 1 μmol g −1 h −1 of crystalline Ta 2 O 5 (C Ta 2 O 5 ), 30±2 μmol g −1 h −1 of mixture with crystalline Ta 2 O 5 and amorphous Na x Ta y O z (C Ta 2 O 5 /Am-Na x Ta y O z ), and even 4.6 × 10 −4 μmol g −1 h −1 for commercial TiO 2 . This observation is beneficial from the short diffusion paths of amorphous state for charge carriers, amount of catalytic sites, and stronger reducing ability. These findings develop a novel and efficient pathway towards synthesizing the different CCM of tantalum-containing compounds under hydrothermal conditions and could open opportunities for further investigating the photocatalytic property of tantalum-containing materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acrylate-vinylidene chloride copolymers were doped with a good RTP molecule. • RTP could detect the variation of copolymers during maturation. • RTP method was more sensitive to the slight crystallinity variation than XRD and FTIR. • The dynamic variation of copolymers could be visually monitored. Unlike fluorescence, room-temperature phosphorescence (RTP) has never been utilized to monitor the dynamic variation of polymer. In the present study, acrylate-vinylidene chloride (VDC) copolymers were doped with a good RTP molecule, N -hydroxyethyl 4-bromo-1,8-naphthalimide (HBN). During the maturation process, marked RTP-intensity enhancement of HBN was observed due to the crystallinity increase of copolymers, verified by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). For ensuring the more efficient RTP emission of HBN, copolymers with a higher content of crystallizable VDC segments and a more polar acrylate comonomer, i.e. methyl acrylate (MA) were preferred. According to the RTP characterizations, the following deductions could be obtained: (1) Maturation for 8–9 days at room temperature was needed for the copolymers with a high VDC content to ensure the complete crystallization; (2) Raising the maturation temperature to 50 and 70 °C not only accelerated the crystallization rate, but also increased the crystallinity of copolymers; (3) RTP method was more sensitive to the slight crystallinity variation than XRD and FTIR. Moreover, the dynamic maturation processes of acrylate-VDC copolymers could be also visually monitored through contacting with certain organic solvents that led to the emission color transition from orange to blue. [ABSTRACT FROM AUTHOR]

The evolution of localized stress/strain gradients and their role in the mechanical stability of heterostructured materials remains puzzled. The rapid progress of synchrotron-based X-ray diffraction methods with a high real and reciprocal spatial resolution provides powerful tools for characterizing multiscale stresses in crystalline materials. We illustrate groundbreaking developments in high-energy X-ray diffraction and X-ray microdiffraction techniques for characterizing the localized stress/microstructural gradients, which are critically assessed in their applications to study the mechanical heterogeneity of heterostructured materials. [ABSTRACT FROM AUTHOR]

Beta-manganese dioxide (β-MnO) microrods were hydrothermally synthesized from ammonium persulfate [(NH)SO] solution using manganese sulfate (MnSO) as reductant at 180 °C for 3 h. The characterizations, including X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, showed that the crystallinity and morphology of the as-synthesized samples were well-defined β-MnO microrods with the diameters of about 100 nm and lengths of about 2-4 μm. To explore the optimal degradation conditions, the as-synthesized β-MnO microrods were employed into the degradation of methyl orange dye solution with the concentration of 20 mg/L in the presence of H with pH values equalling 1.0, 1.5, 2.0, 3.0, 5.0, and 7.0, respectively. The results indicate that the degradation efficiency could reach 98% after 9 min at the pH value of 1.0 or 2.0. Also, the lower the pH value, the higher the degradation efficiency. Based on these experimental results, a proper mechanism of the degradation process of methyl orange is proposed and the rationality of the mechanism is further investigated through the scientific control tests. [ABSTRACT FROM AUTHOR]

Sphere-like MnS hierarchical microstructures were successfully synthesized by a simple hydrothermal approach, which are composed of the size tunable and self-assembled nanoparticles. These hierarchical microspheres are γ-MnS phase, which is confirmed by X-ray diffraction (XRD) results, and the stoichiometry of MnS microspheres is checked by XPS measurement. Morphological studies performed by scanning electron microscopy (SEM) method show that the as-prepared γ-MnS samples are hierarchical microspheres. The size and morphology of composed nanoparticles can be turned by the concentration of L-Cystein molecules. Here, L-Cystein not only plays a role of sulfur source but also capping agent. Furthermore, a rational mechanism about the formation and evolution of the products is proposed. The present work shows that the origin of the observed difference of magnetic properties is due to the morphology difference of MnS crystals. [ABSTRACT FROM AUTHOR]

By utilizing the hydrothermal in situ acylation of organic acids with N 2 H 4 , three acylhydrazidate-coordinated compounds [Mn(L1) 2 (H 2 O) 2 ] (L1 = 2,3-quinolinedicarboxylhydrazidate; HL1 = 2,3-dihydropyridazino[4,5- b ] quinoline-1,4-dione) 1 , [Mn 2 (ox)(L2) 2 (H 2 O) 6 ]·2H 2 O (L2 = benzimidazolate-5,6-dicarboxylhydrazide; HL2 = 6,7-dihydro-1H-imidazo[4,5- g ]phthalazine-5,8-dione; ox = oxalate) 2 , and [Cd(HL3)(bpy)] (L3 = 4,5-di(3′-carboxylphenyl)phthalhydrazidate; H 3 L3 = 6,7-dihydro-1H-imidazo[4,5- g ]phthalazine-5,8-dione; bpy = 2,2′-bipyridine) 3 , as well as two acylhydrazide molecules L4 (L4 = oxepino[2,3,4- de :7,6,5- d ′ e ′]diphthalazine-4,10(5H,9H)-dione) 4 and L5 (L5 = 4,5-dibromophthalhydrazide; L5 = 6,7-dibromo-2,3-dihydrophthalazine-1,4-dione) 5 were obtained. X-ray single-crystal diffraction analysis reveals that (i) 1 only possesses a mononuclear structure, but it self-assembles into a 2-D supramolecular network via the N hydrazine H ⋯ N hydrazine and Ow H ⋯ O hydroxylimino interactions; (ii) 2 exhibits a dinuclear structure. Ox acts as the linker, while L2 just serves as a terminal ligand; (iii) In 3 , L3 acts as a 3-connected node to propagate the 7-coordinated Cd 2 + centers into a 1-D double-chain structure; (iv) 4 is a special acylhydrazide molecule. Two OH groups for the intermediates 3,3′-biphthalhydrazide further lose one water molecule to form 4 ; (v) 5 is a common monoacylhydrazide molecule. Via the N hydrazine H ⋯ O hydrazine , O hydroxylimino H ⋯ O acylamino and the π ⋯ π interactions, it self-assembles into a 2-D supramolecular network. The photoluminescence analysis reveals that 4 emits light with the maxima at 510 nm. [ABSTRACT FROM AUTHOR]

Microstructural and compositional evolution of nanoporous silver (NPS) during dealloying of rapidly solidified Mg 65 Ag 35 alloy in the 1 wt% HCl solution has been investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray analysis. The amount of MgAg phase decreases and that of f.c.c. Ag increases with increasing dealloying time, and no intermediate phase occurs during dealloying. The residual Mg content in NPS decreases with increasing dealloying time, following an exponential decay formula. The coarsening of ligaments in NPS with dealloying time follows a nonlinear relationship, and the coarsening exponent ( n ) is ∼4.8 for the dealloying of Mg 65 Ag 35 . In addition, the activation energy is 55.7 ± 2.9 kJ mol −1 for the chemical dealloying of the rapidly solidified Mg 65 Ag 35 alloy in the HCl solution. [ABSTRACT FROM AUTHOR]

The design of luminescent coordination polymers (LCPs) as sensors for the detection of molecules and ions constitutes an active area of research. Through the introduction of a secondary bis-pyridine-bis-amide ligand, two 3D unique LCPs [Zn(H 2 bpta)] (1) and [Zn(3-bpcha)(bpta) 0.5 ]·H 2 O (2), where 3-bpcha denotes N , N′ -bis(3-pyridyl)cycloheximide and H 4 bpta represents 2,2′,4,4′-biphenyltetracarboxylic acid, were successfully synthesized via the hydrothermal method. Both of these LCPs were characterized by single-crystal X-ray diffraction, FT-IR, and powder X-ray diffraction patterns, which reveal that these LCPs possess two different 3D frameworks. Furthermore, a series of luminescence recognition tests proved that 1 and 2 can act as potential sensing materials for the detection of Fe3+ ions and nitro compounds in aqueous environments. [Display omitted] (I) Two 3D unique LCPs were successfully synthesized via the hydrothermal method. (II) The effect of secondary ligand on LCPs had been investigated in detail. (III) The detection limits of Fe3+ ion were 103 ​ μ M for LCP 1 and 10 ​μM for LCP 2. (IV) The detection limits of NB were found to be 103 ​ μ M for 1 and 10 ​μM for 2. (V) LCPs can act as fluorescent sensors for Fe3+ ions and nitro compounds. Two Zn-based LCPs have been synthesized and characterized, which display remarkable luminescent sensing properties The LCPs can be served as outstanding candidates in the selective sensing of Fe3+, NB and NM under low detection limits. [ABSTRACT FROM AUTHOR]

In this paper, we synthesized a new cathode material (CuBiS) by a solvothermal method for high-performance lithium-sulfur batteries. CuBiS with a unique flower structure was characterized using the X-ray diffraction, energy-dispersive X-ray spectrometer, and scanning electron microscopy. It is shown that the CuBiS/S flower exhibits a high initial capacity of 1343 mAh g at 0.2 C, and although a capacity fade in subsequent cycles occurs due to polysulfide dissolution and shuttle mechanism, 487 mAh g at 0.2 C can be retained after 100 cycles with the 90-95 % coulombic efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we report a facile method to prepare a twins-structural Sn@C core–shell composite that is used as anode materials for lithium-ion batteries. Its surface morphology and microstructures were characterized by the scanning electron microscope, X-ray diffraction, and transmission electron microscope. The electrochemical performances of Sn@C were measured by charge–discharge tests, cyclic voltammogram, and electrochemical impedance spectra. It is shown that such a composite exhibits a high initial specific capacity of 970 mA h g−1and a capacity retention of 400 mA h g−1after 50 cycles at the current density of 100 mA g−1. [ABSTRACT FROM AUTHOR]

A ternary composite of Ag/MnFe 2 O 4 /reduced graphene oxide (RGO) was synthesized by a facile hydrothermal method. The morphology, microstructure, magnetic and electromagnetic properties of as-prepared Ag/MnFe 2 O 4 /RGO composite were characterized by means of XRD, TEM, XPS, VSM and vector network analyzer. The maximum reflection loss (R L ) of Ag/ MnFe 2 O 4 /RGO composite shows maximum absorption of −38 dB at 6 GHz with the thickness of 3.5 mm, and the absorption bandwidth with the R L below −10 dB is up to 3.5 GHz (from 3.7 to 7.2 GHz). The result demonstrates that the introduction of Ag significantly leads to the multiple absorbing mechanisms. It is believed that such composite could serve as a powerful candidate for microwave absorber. [ABSTRACT FROM AUTHOR]

The La 3+ doped spinel ferrites, Ni 0.8 Zn 0.2 La x Fe 2− x O 4 , were prepared by a sol–gel method. The samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). Results show that La 3+ can completely substitute into the lattice of Ni 0.8 Zn 0.2 Fe 2 O 4 and exist mostly in the form of lamellar structure. Ni 0.8 Zn 0.2 La x Fe 2− x O 4 ( X =0–0.1) show the behaviors of the soft magnets and the saturation magnetization ( M s ) decreases with the increasing of La 3+ content. The electromagnetic property of Ni 0.8 Zn 0.2 La 0.06 Fe 1.94 O 4 is below −10 dB at 3.1–5.9 GHz and its minimum loss value is −15.43 dB at 5.1 GHz. Therefore, the introduction of La 3+ improves the microwave absorbing properties of Ni 0.8 Zn 0.2 Fe 2 O 4 . [ABSTRACT FROM AUTHOR]

Characteristic samples from the No. 1 ore body of the Jinlong bauxite deposit in Guangxi Province, China, were assessed to determine their chemical composition using whole-rock geochemical analysis, their mineral components using X-ray diffraction, their thermal characteristics via differential thermal analysis, thermogravimetry and differential thermogravimetry, and their dissemination characteristics by scanning electron microscopy/energy-dispersive spectrometry. The results show that the average AlO content in the Jinlong bauxite deposit is 41 % and that the AlO/SiO ratio is approximately 2.17, and thus, the ore may be defined as low-grade bauxite. The main minerals found in the ore were diaspore (20.3-43 %), gibbsite, clays and hematite. In differential thermal analysis results, the bauxite samples exhibit two distinct endothermic peaks, with the dehydration of gibbsite occurring in the 200-260 °C range and the dehydration of diaspore occurring in the 524-550 °C range. Thermogravimetry and differential thermogravimetry indicate four decomposition stages: evaporation of adsorbed water (50-160 °C), gibbsite decomposition (190-280 °C), goethite decomposition (190-280 °C) and diaspore dehydroxylation (460-580 °C). The diaspore belongs to the orthorhombic dipyramidal class and exists primarily in three dissemination forms-euhedral and subhedral grain, bean and oolitic shaped, and aphanitic and microcrystalline aggregates, and is always accompanied by kaolinite and pyrophyllite. [ABSTRACT FROM AUTHOR]

The structure of La doped BiFeO 3 , prepared by the conventional hydrothermal method, were investigated at room temperature using X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) spectroscopy. The XAFS spectra showed that La in fact substitute the Bi site of secondary nanosized particles with orthorhombic symmetry instead of the long-believed rhombohedral R 3 c phase at low-content doping. The pressure-induced phase-transition sequences of La-doped BiFeO 3 , which mixed nanoscale orthorhombic symmetry in the R 3 c crystal structure were investigated using synchrotron radiation X-ray diffraction up to 27.3 GPa. Our experimental data clearly showed that rohombohedral (R 3 c) phase first transforms to monoclinic (C 2/ m) phase at 6.5 GPa, then to orthorhombic (Pnma) phase at 13.5 GPa, and the coexistence of multiple intermediate phases are observed before two transitions, revealing that the doping-induced nanoparticles with orthorhombic structure did drive the change in symmetry and transition pressure. • Only few La is actually doped into the lattice of BiFeO 3 by hydrothermal method. • La substitution induces a nanoscale phase transition from R3c to orthorhombic symmetry by XAFS results in BiFeO 3. • The secondary nanosized particles in La-doped BiFeO 3 have influence on the phase transition under pressure. [ABSTRACT FROM AUTHOR]

Tm3+ singly- and Dy3+/Tm3+ co-doped CaLaGa 3 O 7 phosphors were prepared successfully by a high-temperature solid-state reaction method and their structure, spectroscopic properties, as well as energy transfer processes between Dy3+ and Tm3+ were studied. The XRD measurements show that all the prepared phosphors have a tetragonal structure. The emission proved that under excitation by 355 nm, 455 nm blue light was obtained in Tm3+: CaLaGa 3 O 7 phosphor with a high color purity (99%). For Dy3+/Tm3+: CaLaGa 3 O 7 , the emission spectra exhibited the typical yellow emissions of Dy3+ and blue light of Tm3+. More importantly, the relative emission intensity of Dy3+ and Tm3+ can be varied by modifying the concentration of Tm3+ and the exciting wavelength, indicating that the luminescence color is tunable. Further, optimal white-light emission was achieved when co-doped 0.01 Tm3+ and 0.02 Dy3+ under 355 nm excitation. Meanwhile, the CIE chromaticity coordinates, color temperature value and color purity of the 0.02 Dy3+/0.01 Tm3+: CaLaGa 3 O 7 phosphor were calculated to be (x = 0.3321, y = 0.3231), 5515 K and 7.18%, respectively, which are close to the standard white-light illumination. Moreover, the study on the decay curves indicates that mutual energy transfers between Dy3+ and Tm3+ take place in the Dy3+/Tm3+: CaLaGa 3 O 7 phosphor. The above findings suggest that the prepared phosphors have potential applications in light emission devices. [ABSTRACT FROM AUTHOR]

Ni x Al y Mn 3− x − y O 4 (0 < x < 0.6; 0 < y < 0.3) series NTC chip thermistors with homogeneous chemical compositions and high-pure spinel phases were fabricated via a tape casting-lamination-sintering process. The multi-variate cation distribution model was established as (Mn 1 - x + v 2 + Ni x - v 2 +) Mn 2 - 2 v - y 3 + Mn v 4 + Ni v 2 + Al y 3 + O 4 (0 < v < 0.5). The conduction mechanism was proposed based on a nearest neighbor hopping (NNH) model. They were verified coherently by cation-oxyanion chemical compositions (XRF/EDS), valence states (XPS), phase structures and Rietveld refinements (XRD), IR vibrations and electrical analyses. The obtained NTC chips were well suitable for commercial applications with a high reliability and with regulable ρ 25 (4080 ± 135 ∼ 15,760 ± 526 Ω cm) and B 25/50 (4016 ± 20 ∼ 4251 ± 13 K). • Ni x Al y Mn 3− x − y O 4 (0 < x < 0.6; 0 < y < 0.3) specimens were fabricated via a tape casting-lamination-sintering process. • The multi-variate cation distribution model was established. • The conduction mechanism was proposed based on a nearest neighbor hopping (NNH) model. • MNA-series NTC chip thermistors have a high reliability and apply to the commercial production in microelectronic industry. [ABSTRACT FROM AUTHOR]

LiNi0.815Co0.15Al0.035O2 (NCA) has attracted a lot of attention owing to its high specific capacity and low cost. The problems of capacity loss and interface side reaction during the long cycle hinder the application of NCA cathode materials. In this work, WO3-coated LiNi0.815Co0.15Al0.035O2 cathode materials were successfully prepared, which greatly improved the electrochemical properties of the NCA. Results of XRD show that the WO3 coating has no significant effect on the structure of the NCA samples. Results of XPS show that WO3 coating is beneficial to reduce the content of residual alkali substance on the surface of the NCA. In addition, the first discharge specific capacity of NCA@2wt%WO3 is 174.96 mAh g − 1 at a current density of 1.0 C, with a capacity retention rate of 89.94% after 200 cycles. The discharge specific capacity of NCA@2wt%WO3 is 137.74 mAh g − 1 at 5.0 C. The coating of WO3 effectively improves the electrochemical performance of NCA cathode materials. [ABSTRACT FROM AUTHOR]

Two new organically templated borates, [(1,10-phen)(H3BO3)2] (1) and [2-EtpyH][(B5O6(OH)4] (2), were synthesized under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, FT-IR, elemental analyses and thermogravimetry. Complex 1 is a co-crystal component in which B(OH)3 molecules form crinkled tapes via hydrogen bonds, which in turn are packed in a two-dimensional framework with 1,10-phen molecules sandwiched between the framework of crinkled chains. The structure of complex 2 is composed of 2-ethylpyridinium cations [2-EtpyH]+ and pentaborate anions [B5O6(OH)4]– which are linked together with hydrogen bonds to form a three-dimensional supramolecular framework. The templating [2-EtpyH]+ cations are situated in the cavities arising from the supramolecular pentaborate framework and interact also with the inorganic framework through hydrogen bonds. [ABSTRACT FROM AUTHOR]

This study is carried out in the context of III-V semiconductor monolithic integration on silicon for optoelectronic device applications. X-ray diffraction is combined with atomic force microscopy and scanning transmission electron microscopy for structural characterization of GaP nanolayers grown on Si. GaP has been chosen as the interfacial layer, owing to its low lattice mismatch with Si. But, microtwins and antiphase boundaries are still difficult to avoid in this system. Absolute quantification of the microtwin volume fraction is used for optimization of the growth procedure in order to eliminate these defects. Lateral correlation lengths associated with mean antiphase boundary distances are then evaluated. Finally, optimized growth conditions lead to the annihilation of antiphase domains within the first 10 nm. [ABSTRACT FROM AUTHOR]

Self-assembly of NiII/CoIIwith 4,4′-sulfonyldibenzoic acid (H2E1) and 1,4-bis(1,2,4-triazole-1-ylmethyl)benzene (pbtx) has produced 3-D interpenetrated polythreading networks with non-trivial linkages, [{Ni(pbtx)(E1)(H2O)}·H2O]n(1) and [{Co(pbtx)(E1)(H2O)}·H2O]n(2), respectively. Single-crystal X-ray diffraction analyses revealed that1and2are isomorphous and isostructural. Complexes1and2possess a 2-D grid layer consisting of metal ions bridged by pbtx ligands and entirely deprotonated E12−ligands, which led to the formation of 2-fold interpenetrated polythreading networks. The interpenetrated networks were further bridged by C–H⋯O and O–H⋯O hydrogen bonds to generate their 3-D frameworks. Further characterizations including elemental analysis, FT-IR, XPRD, and Thermogravimetric analysis have been studied. Two 2-fold interpenetrated polythreading networks, [{Ni(pbtx)(E1)(H2O)}·H2O]n(1) and [{Co(pbtx)(E1)(H2O)}·H2O]n(2), were constructed by aromatic polycarboxylic acid H2E1 (H2E1 = 4,4′-sulfonyldibenzoic acid) and pbtx (pbtx = 1,4-bis(1,2,4-triazole-1ylmethyl)benzene).1and2show distinctive new interpenetrated structure of two identical single nets interlocked with each other via rotaxane-like links. [ABSTRACT FROM PUBLISHER]

A description of the rocking curve in diffraction enhanced imaging (DEI) is presented in terms of the angular signal response function and a simple multi-information retrieval algorithm based on the cosine function fitting. A comprehensive analysis of noise properties of DEI is also given considering the noise transfer characteristic of the X-ray source. The validation has been performed with synchrotron radiation experimental data and Monte Carlo simulations based on the Geant4 toolkit combined with the refractive process of X-rays, which show good agreement with each other. Moreover, results indicate that the signal-to-noise ratios of the refraction and scattering images are about one order of magnitude better than that of the absorption image at the edges of low- Z samples. The noise penalty is drastically reduced with the increasing photon flux and visibility. Finally, this work demonstrates that the analytical method can build an interesting connection between DEI and GDPCI (grating-based differential phase contrast imaging) and is widely suitable for a variety of measurement noise in the angular signal response imaging prototype. The analysis significantly contributes to the understanding of noise characteristics of DEI images and may allow improvements to the signal-to-noise ratio in biomedical and material science imaging. [ABSTRACT FROM AUTHOR]

Cryptomelane type manganese oxide α-MnO 2 and Ni doped KMn 8 O 16 nanostructures were synthesized by water-bathing methods at 80 °C for 24 h using NiSO 4 ·H 2 O as the dopant sources. The structures, morphologies and physical properties were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results show that the products are Ni doped KMn 8 O 16 nanorods after the introduction of NiSO 4 ·H 2 O during the reaction process. The electromagnetic characteristics and microwave absorption properties of the materials were carried out with a vector network analyzer (VNA) and the transmission line (TML) theory. The dielectric loss and microwave absorption properties of the cryptomelane materials are improved after Ni doping. The thickness dependent reflection loss shows that the peak frequency and effective absorption bandwidth all decrease with the increasing material thickness. With the increase of Ni doping concentration, the peak frequency shifts to higher frequency bands and the effective absorption bandwidth increases. The electromagnetic performance of cryptomelane can be attributed to its unique tunnel structures and the improvement of Ni doping can be due to the enhanced electromagnetic polarization. [ABSTRACT FROM AUTHOR]

By employing the hydrothermal in situ acylation of N 2 H 4 with aromatic polycarboxylic acids, three new acylhydrazidate-extended coordination polymers (CPs) [Pb 2 (3-cppth) 2 (phen) 2 ] (3-cppth = 4-(3-carboxyphenoxy)phthalhydrazidate, phen = 1,10-phenanthroline) 1 , [Cd(4-cppth)(bpy)(H 2 O)]·H 2 O (4-cppth = 4-(4-carboxyphenoxy)phthalhydrazidate, bpy = 2,2′-bipyridine) 2 and [Zn(dcpth) 2 ] (dcpth = 4,5-dichlorophthalhydrazidate) 3 were obtained. X-ray single-crystal diffraction analysis revealed that (i) compound 1 possesses a one-dimensional (1-D) double-chain structure. Via the N–H⋯O interactions between the neighboring acylamino groups, two such double chains aggregate together into a 1-D supramolecular chain. The phen molecules are distributed on the outer side of the supramolecular chain, hindering the further extension of the 1-D supramolecular chain; (ii) compound 2 exhibits a 1-D zigzag-type single-chain structure. Via the hydrogen-bonded interactions between the acylamino groups, compound 2 self-assembles into a two-dimensional (2-D) grid-like supramolecular layer network. The π⋯π interactions between the bpy molecules are observed between the supramolecular layers; (iii) in compound 3 , two hydroxylimino groups for the dcpth I molecules link first the Zn 2+ ions into a dimer, which can be viewed as a tetrahedral node. The dcpth II molecules act as the linkers, extending the tetrahedral nodes into another 1-D double-chain structure, different from that of compound 1 . [ABSTRACT FROM AUTHOR]

Two new trihydrazine bridged CoII chain compounds have been synthesized and magnetically characterized. The two compounds are both composed of [Co-(N2H4)3]2+ chains. One exhibits antiferromagnetic ordering behavior while the other behaves as a single-chain magnet (SCM) at low temperature. [ABSTRACT FROM AUTHOR]

Abstract: The stable and crystalline phase Ln (Ln=Sm, Er, Gd, Dy, and Eu) doped La(OH)3 (La(OH)3:Ln3+) nanorods were synthesized by a facile hydrothermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to examine the microstructure and morphology. The analysis reveals that the obtained compounds are one-dimensional (1D) rod-like nanostructures. The photodegradation of La(OH)3:Ln3+ nanorods was tested by measuring the degradation of azo dye Congo red (CR). The experiments demonstrated that La(OH)3:Ln3+ nanorods degraded CR much faster than undoped La(OH)3 nanorods and the photodegradation efficiency of La(OH)3:Ln3+ nanorods was significantly higher than that of undoped La(OH)3 nanorods. [Copyright &y& Elsevier]

Graphene nanosheets-tungsten oxides (tungsten oxide/tungsten oxide hydrate mixture) (GNS-W) composite was successfully synthesized using a facile approach. WO3/WO3·H2O mixtures were deposited on the graphene nanosheets (GNS) to form the GNS-W composite. The GNS-W composite was characterized by X-ray diffraction (XRD), Raman spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The as-prepared GNS-W composite was directly fabricated into a supercapacitor electrode for potential energy storage application, and electrochemically tested by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The GNS-W composite electrode exhibits a better electrochemical performance than that of the WO3/WO3·H2O mixtures electrode. A high specific capacitance of about 143.6Fg−1 at a current density of 0.1Ag−1 for the GNS-W composite delivers significant improvement than that for the WO3/WO3·H2O mixtures and GNS electrodes. The impedance studies also suggest that the GNS-W composite electrode shows the lower resistance and high conductivity due to the good interaction between the graphene nanosheets and the WO3/WO3·H2O mixtures. The good electrochemical performance for the GNS-W composite may be attributed to the interaction between the WO3/WO3·H2O mixtures and the edges of graphene nanosheets, which increases the ion diffusion rate as well as the conductivity. [ABSTRACT FROM AUTHOR]

Under the hydro(solvo)thermal conditions, the reactions of metal halides with organic N-heterocyclic molecules produced three new organically modified metal halides [tmbp][CuBr] (tmbp = N, N, N′, N′-tetramethyl-4,4′-bipiperidinium) 1, [H(dmbpp)][PbI] (dmbpp = dimethyl-1,3-bis(4-piperidyl)propane) 2 and [PbI(bpp)] 3 (bpp = 1,3-bis(4-pyridyl)propane). It is noteworthy that tmbp in compound 1 originated from the in situ alkylation of bp with CHOH (bp = 4,4′-bipiperidine). The mechanism study indicates that H and Br play a key role in the alkylation reaction. X-ray single-crystal diffraction analysis revealed that (i) compounds 1 and 2 are the organically templated halometallates. Both possess the 1D chain structures. The 1D chain of compound 1 can be regarded as a linear arrangement of CuBr tetrahedra by sharing the edges, whereas that of compound 2 can be considered as an endless extension of PbI octahedra by sharing the faces; (ii) compound 3 is the 1:1 adduct of PbI and bpp. The PbI chain shows a linear shape. Bpp serves as the connector, propagating the PbI chains into a 2D layer network of compound 3. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: The LiFe0.92PO4 including Fe vacancy defects was prepared as performance-improved cathode material for lithium-ion battery by a carbothermal reduction method. A combination of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM), electrochemical testing, and first-principles calculations was used to determine and rationalize the physical and electrochemical characterizations of LiFe0.92PO4. The XRD, FTIR and XPS results indicated that Fe vacancy defects had been successfully incorporated into the parent olivine phase of LiFe0.92PO4 and did not affect its olivine lattice structure. Especially, the LiFe0.92PO4 sample exhibited a discharge capacity of 69.0 mAh g−1 at 10C and capacity retention ratio of 96% after 100 cycles at various rates, implying excellent rate capability and cycling stability. Moreover, the lithium ion migration channels, energy band structures, densities of states, and charge densities of LiFePO4 and LiFe0.92PO4 were investigated by first-principles calculations. The results suggest that the higher lithium ion conduction and electronic conductivity of LiFe0.92PO4 is attributed to Fe vacancy defects. [Copyright &y& Elsevier]

The structure of La doped BiFeO 3 , prepared by the conventional hydrothermal method, were investigated at room temperature using X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) spectroscopy. The XAFS spectra showed that La in fact substitute the Bi site of secondary nanosized particles with orthorhombic symmetry instead of the long-believed rhombohedral R 3 c phase at low-content doping. The pressure-induced phase-transition sequences of La-doped BiFeO 3 , which mixed nanoscale orthorhombic symmetry in the R 3 c crystal structure were investigated using synchrotron radiation X-ray diffraction up to 27.3 GPa. Our experimental data clearly showed that rohombohedral (R 3 c) phase first transforms to monoclinic (C 2/ m) phase at 6.5 GPa, then to orthorhombic (Pnma) phase at 13.5 GPa, and the coexistence of multiple intermediate phases are observed before two transitions, revealing that the doping-induced nanoparticles with orthorhombic structure did drive the change in symmetry and transition pressure. • Only few La is actually doped into the lattice of BiFeO 3 by hydrothermal method. • La substitution induces a nanoscale phase transition from R3c to orthorhombic symmetry by XAFS results in BiFeO 3. • The secondary nanosized particles in La-doped BiFeO 3 have influence on the phase transition under pressure. [ABSTRACT FROM AUTHOR]