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1.
Cubic and octahedral Cu2O nano‐ and microcrystals were selectively synthesized via a simple wet chemical reduction route at room temperature, with CuCl2 and NaOH as starting reactants, and ascorbic acid or hydrazine hydrate as the reducer. Hydrazine hydrate could be preferentially adsorbed on different crystal faces of Cu2O, affecting the growth rate along the 〈100〉 to that along the 〈111〉 direction, which resulted in the formation of octahedral Cu2O crystals. When ascorbic acid was used as the reducer, the growth rate along the 〈100〉 to that along the 〈111〉 direction was different, which resulted in the formation of cubic Cu2O crystals. The size of cubic and octahedral Cu2O crystals could be varied by adjusting the molar ratio of OH– to Cu2+. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
2.
The influence of solvents on the hydrothermal formation of one‐dimensional (1D) magnesium hydroxide (Mg(OH)2) was investigated in this paper. Uniform 1D Mg(OH)2 with a length of 10‐20 μm, a width of 100‐200 nm and a preferential growth along [110] direction have been synthesized by treating magnesium oxysulfate (5Mg(OH)2·MgSO4·3H2O, abbreviated as 513MOS) nanowires in NaOH ethanol solution at 180 °C for 2.0 h. The experimental results indicated that the solvent of ethanol and NaOH concentration were essential for the conversion of 513MOS nanowires to 1D Mg(OH)2. The slow release of MgSO4 from 513MOS and the heterogenous precipitation of Mg(OH)2 at the defects left by MgSO4 dissolution promoted the formation of 1D Mg(OH)2. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
3.
L. Zhu Y. Chen Y. Sun Y. Cui M. Liang J. Zhao N. Li 《Crystal Research and Technology》2010,45(4):398-404
Using the ionic liquid (IL), 1‐butyl‐3‐methyl‐imidazole tetrafluoroborate, and the precursor Cu7Cl4(OH)10·H2O, series of phase‐manipulable Cu‐based nanomaterials were synthesized by hydrothermal and microwave assisted routes, respectively. The structural characters of the as‐prepared CuO, CuO/Cu2O composites and pure Cu nanoparticles were investigated by XRD, SEM, TEM and HRTEM, and their surface photovoltaic properties were studied by surface photovoltage spectra. Via hydrothermal route Cu2+ ions were found to be reduced gradually into Cu+ and subsequently Cu0 with increasing the IL, and various phase ratio of CuO, Cu2O and Cu composite nanosheets and pure Cu nanoparticles were obtained. This implies that the IL could function as both a reductant in the oxygen‐starved condition and a template for the nanosheet products. The 1H‐NMR result of the IL supports it being a reductant. In microwave assisted route, however, only monoclinic single crystalline CuO nanosheets were obtained, which indicates the IL being a template only in oxygen‐rich condition. Therefore, the crystal phase, composition and morphology of the Cu‐based products could be controlled by simply adjusting the quantity of the IL and oxygen in solution routes. The molecular structure of the IL after oxidation reactions was investigated by 1H‐NMR and a possible reaction mechanism was proposed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
4.
J. H. Zheng J. L. Song X. J. Li Q. Jiang J. S. Lian 《Crystal Research and Technology》2011,46(11):1143-1148
Zn1‐xCux O powders were synthesized by using sol‐gel method. Electronic band structure and ferromagnetic properties of Zn1‐xCux O powders were studied experimentally and theoretically. The simulations are based upon the Perdew‐Burke‐Ernzerhof form of generalized gradient approximation within the density functional theory. Zn1‐xCux O shows dilute ferromagnetism, as a saturated magnetization of 0.9×10‐3emu/g was observed for Zn0.95Cu0.05O powders. The strong p ‐d hybridization between Cu and its four neighbouring O atoms is responsible for the ferromagnetism. Comparing with ZnO whose Fermi level locates at the valence band maximum, the Fermi level of the Zn1‐xCux O shifts upward into the valence band and hence the Zn1‐xCux O system exhibits theoretically a p ‐type metallic semiconducting property. The Zn1‐xCux O system may be a potential candidate in spintronics. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
5.
Wei Wang Zhigang Liao Yi Wang Xiang Wu Fengyu Qu Xu Zhang 《Crystal Research and Technology》2011,46(3):300-304
Highly symmetric 26‐facet polyhedral microcrystals of cuprous oxide (Cu2O) are successfully synthesized through a facile low temperature hydrothermal reaction. These polyhedra are constructed by well‐developed {100}, {110} and {111} crystallographic faces. The obtained microstructures were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Ultraviolet‐Visible (UV‐Vis) absorption spectrum. Cetyltrimethyl ammonium bromide (CTAB) and ethylenediaminetetraacetic acid disodium (EDTA‐2Na) have been confirmed to be necessary additives to the development of these perfect polyhedra. The growth process of the 26‐facet Cu2O polyhedra is depicted on the grounds of the time‐dependent experiments. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
6.
A. Yilmaz P. Camurlu L. Tatar Yldrm D. Ksakürek D. Ülkü 《Crystal Research and Technology》2006,41(8):829-835
Diaquatetrakis(N‐methylimidazole)Ni(II)(2,4,6‐tribromophenol), Ni(H2O)2(C3N2(CH3))4.2(C6H3Br3O), was synthesized via reaction of nickel sulphate and 2,4,6‐tribromophenolate in aqueous media in the presence of N‐methyl imidazole and sodium hydroxide. The complex crystalizes in the triclinic space group P1 with one formula unit of Ni(C3H3N2(CH3))4(H2O)2.2(C6H3Br3O) in the cell. The coordination around the Ni(II) ion is a slightly distorted octahedron, involving four N atoms from four different di(N‐methyl imidazole) ligand in the basal plane. The two oxygen atoms of the water molecules located at the apical positions result in an octahedral coordination. The two tribomophenol groups in the unit cell are connected via hydrogen‐bonds to the atoms of the coordination sphere, to build one dimensional chains along the a‐axis. For characterization of complex FTIR, UV spectroscopy, DSC and TGA thermal analysis were performed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
7.
Jian Wu 《Crystal Research and Technology》2008,43(10):1097-1100
A supramolecular compound, {[CuMn(pydc)2(H2O)5]·2H2O} ( 1 ) (pydc = pyridine‐2,6‐dicarboxylate dianion), has been synthesized and characterized by single‐crystal X‐ray diffraction. Single‐crystal X‐ray analysis reveals that it crystallizes in the triclinic space group P‐1, a = 8.4763(17) Å, b = 9.7715(19) Å, c = 13.909(3) Å, α =101.234(3)°, β =102.520(3)°, γ= 97.375(4)°. Two mixed‐metal ions exhibit similar coordinated geometries with octahedron. 1 possesses a 3‐D unusual supramolecular network featuring 1D water tape. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
8.
Cuprous oxide (Cu2O) microcrystals with various morphologies were prepared under mild hydrothermal condition. The samples were characterized by means of XRD, SEM, and UV/DRS. The morphology of the as‐prepared Cu2O microcrystals typically had cubic symmetry and the morphology evolution from radial, six hollow branches to truncated octahedra (again cubic) were realized by adding acetic acid. The peak relative intensity of XRD pattern shows that the exposed planes of samples is consistent with their morphology. A possible growth mechanism of Cu2O microcrystals is also proposed. The behavior of adsorption and photocatalysis of Cu2O microcrystals was investigated by degrading methyl orange (MO) in aqueous solution. The results show that the as‐prepared Cu2O radial six hollow branches microcrystals with exposed {110} planes have higher degradation efficiency to methyl orange (MO) than cubic ones with exposed {100} planes and truncated octahedral with exposed {111} planes microcrystals. 相似文献
9.
Matthias Weil 《Crystal Research and Technology》2007,42(11):1058-1062
Crystals of the double sulfate CaMg2(SO4)3 have been obtained by solid‐state reactions of stoichiometric amounts of anhydrous CaSO4 and MgSO4 in sealed and evacuated silica tubes with chlorine gas as mineraliser. The crystal structure was determined from single crystal X‐ray diffractometer data [P 63/m, Z = 2, a = 8.3072(4), c = 7.3057(8) Å, R [F2 > 2σ (F2)] = 0.0317, wR (F2 all) = 0.0785, 476 structure factors, 33 variable parameters] and consists of distorted [CaO6] octahedra (3 symmetry), [MgO6] octahedra (3 symmetry) and SO4 tetrahedra (m symmetry) as single building units. The structure is made up of 1∞[CaO6/2] chains of face‐sharing [CaO6] octahedra that extend parallel to [001], alternating with columns of face‐sharing [MgO3/1O3/2]2 dimers. Both types of chains are linked via corner‐sharing with SO4 tetrahedra into a three‐dimensional framework structure. Although the compound crystallizes in a new structure type, it is topologically related to the NaZr2(PO4)3 (Nasicon) structure, and a comparative discussion between both structural arrangements is given. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Bis{2,6‐bis (hydroxymethyl) pyridine‐O,O,N} {μ‐bis(2‐hydroxymethylpyridyl) methanolate‐O,N} dicopper(II) di(propionate) (CCDC 143763) has been prepared and studied by single‐crystal X‐ray diffraction methods at 293(2) K. The crystal structure consists of dimeric complex cation, [Cu2(μ‐bhmp)2(bhmpH)2]+2 and propionate anions (bhmp ‐ 2,6‐bis(hydroxymethyl) pyridine; bhmpH ‐ 2‐(6‐hydroxymethylpyridyl) methanolate ) and propionate anions. The complex cation contains two neutral and two monodeprotonated bhmp molecules, each coordinate to one Cu(II) atom in a tridentate chelating manner, via two O atoms and N atom. The monodeprotonated bmph molecules are also tridentate coordinate via N atom and only one O atom, which serve as bridge between two CuO4N2 moieties. The propionate anions are “ fixed” to the complex by the hydrogen bonds. 相似文献
11.
The title compound, C10H8N6O3, was synthesized by the reaction of 3‐(1H)‐1,2,4‐triazole hydrazine with 3‐nitrobenzaldehyde in ethanol. The single crystal structure has been determined by X‐ray analysis. The crystal belongs to monoclinic system, space group p21/c with cell constant, a = 8.0214(17) Å, b = 17.334(4) Å, c = 8.9070(18) Å, V= 1179.4(4) Å3. An intramolecular N—H...O and N—H…N hydrogen bond are observed between the ‐NH group with O atom of the carbonyl group and the ‐NH group with N atom. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
12.
I. V. Zatovsky N. Yu. Strutynska N. S. Slobodyanik V. N. Baumer O. V. Shishkin 《Crystal Research and Technology》2008,43(4):362-368
The crystallization of alkali‐earth phosphates in the melts of Cs2O‐P2O5‐MIIO (MII – Ca, Sr, Ba) pseudo‐ternary systems have been investigated at various Cs/P molar ratios and at fixed value of MII/P equal to 0.15. Type of the phosphate which crystallizes in melts depends on the Cs/P initial ratio. Crystallization fields of CsMIIP3O9, MII2P2O7 and Cs2MIIP2O7 were briefly investigated and characterized. The new diphosphate Cs2CaP2O7 has been obtained and investigated by the single crystal and powder X‐ray diffraction and FTIR‐ spectroscopy. It crystallizes in C 2/m space group, with the following parameters of the monoclinic cell: a = 10.261(2), b = 5.9316(12), c = 7.2404(14) Å, β = 118.54(3)°. The architecture of [CaP2O7]2‐ anionic sublattice, which is built up from [CaO6] octahedra and [P2O7] bitetrahedra, interlinked via the common oxygen vertices, gives rise to formation of hexagonal tunnels along crystallographic direction b, where caesium atoms are located. One of the most remarkable features of the structure is specific positional disorder of the diphosphate group, which is connected with the existence of two equiprobable half‐occupied sites of the bridging oxygen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
13.
In the present report, CuO, Cu2O and Cu have been successfully synthesized through a facile, one‐step hydrothermal method at a relative low temperature by controlling only the concentration of citric acid. Compared with other synthetic methods, the present method is mild, high‐efficient and nontoxic. The crystal structure and morphology of the as prepared samples were characterized by X‐ray diffraction and scanning electron microscopy, respectively. The mechanism for the crystal phase and morphological changes with different citric acid concentrations were discussed. The possible reaction process of the synthesis was also studied on the basis of the experimental results. We hope that this facile, one‐step hydrothermal method could be used in controlling synthesis of other metals and metal oxides under appropriate experimental conditions. 相似文献
14.
T. S. Kayed 《Crystal Research and Technology》2003,38(11):946-950
Lithium‐doped Tl‐based superconductor was prepared by adding an amount of 0.3 mol.% to the Tl1.8Ba2Ca2.2Cu3Ox compound. The usual solid‐state reaction method has been applied under optimum conditions. The x‐ray data of the sample show a tetragonal structure with a high ratio of Tl‐2223 superconducting phase. The sample showed a transition at 125 K and the zero resistance was observed at 117 K. Longitudinal (transport) and transverse (Hall) resistivities were measured at different temperatures under different magnetic fields and the data were interpreted. A positive Hall coefficient was observed at normal state and a sign reversal appears at temperatures lower than the critical temperature. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
15.
X. J. Wang H. L. Liu X. L. Wan J. R. Wang L. L. Chang 《Crystal Research and Technology》2013,48(12):1066-1072
Monoclinic peanut‐like BiVO4 products have been successfully synthesized by a solvothermal method. The volume of CH3COOH and the concentration of NH3·H2O were found to play important roles in the formation of this morphology. The optimal condition for preparation of highly active peanut‐like BiVO4 samples are the volume of CH3COOH, which was 5 ml, and the concentration of NH3·H2O, which was 2 mol/L. The as‐prepared samples were characterized by XRD, SEM, TEM, DRS, BET, and their photocatalytic activity was evaluated by photocatalytic decolorization of a Rhodamine B (RhB) aqueous solution under visible‐light irradiation. The results demonstrated that BiVO4 with peanut‐like morphology was better than that of other BiVO4 samples for photodegradation of RhB. 相似文献
16.
Crystallization of calcium carbonate (CaCO3) crystals by a gas‐liquid diffusion method has been carried out in aqueous solution using a double‐hydrophilic block copolymer (DHBC) poly(maleic anhydride)‐b‐poly(acrylic acid) (PMA‐b‐PAA). The as‐prepared products were characterized with X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), selected area electron diffraction (SAED), high‐resolution transmission electron microscopy (HRTEM) and infrared spectroscopic analysis (FT‐IR). Uniform one‐dimensional calcite micro/nanostructures with different morphologies are fabricated through an assembled process. The influence of PMA‐b‐PAA copolymer concentration on the morphology of calcite nano/microwires is investigated, which plays an important role in the morphological control of building blocks composed of one‐dimensional calcite crystals. The possible formation mechanism of one‐dimensional CaCO3 crystals was discussed. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
17.
The title compound, C22H19N5O2, was prepared and its structure was determined by X‐ray diffraction [CCDC 216074]. The compound crystallizes from ethanol in the orthorhombic system, space group P212121, with unit cell parameters: a =10.048(1) Å, b = 13.935 (2) Å, c =14.607(2) Å, Z =4, and V=2045.3(5) Å3. The crystal structure was solved by direct methods and refined by full‐matrix least‐squares to a final R‐value of 0.0516 with 3621 unique reflections. The central six‐membered ring of the compound has a boat conformation and is not homoaromatic, in which adjacent atoms N1 and N4 deviate from the plane of the ring by 0.4546(33) Å and 0.3786(33) Å, respectively. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
18.
G.M. Kuz'micheva Yu.V. Esaulova A.H.R.M. Alsarraf A.S. Andreenko I.E. Kostyleva E.P. Khlybov T. Palewski 《Crystal Research and Technology》2002,37(6):612-626
Conditions of the synthesis, crystal structures, mechanical properties, electrical resistivities and magnetizations of cuprates with the general formula (Cr,Cu)(Sr,La)2(La,A)Cu2O8‐δ where A=Ca or Sr of 1212‐type and (Cr,Cu)Sr2(Y,Ce)2Cu2O10‐δ of 1222‐type were investigated. The compositions of the cuprates and an amount of the impurity phases in the samples were determined. Rietveld refinement of the structure was carried out. It was found that the formal charges of Cu (FCCu) calculated from the electroneutrality of refined phase compositions do not achieve value optimal for the appearence of superconducting phases. 相似文献
19.
The crystal structure of the orthorhombic copper salt Cu2(OH)3NO3 (natural gerhardtite) has been determined from X-ray diffractometer data by means of three-dimensional Patterson and Fourier syntheses, and refined by difference Fourier syntheses and least-squares methods to a finalR index of 0.097 for 532 reflections. Crystals of Cu2(OH)3NO3 are orthorhombic:a=6.087(2),b=13.813(4),c=5.597(2) Å,Z=4, space groupP212121. The Cu atoms form deformed hexagonal pseudocells (010). Each Cu(1) ion is surrounded by an approximately square planar arrangement of four OH ions at 1.929, 1.952, 1.993 and 1.998 Å and by two O (of NO3 ions) at 2.359 and 2.480 Å, completing a deformed coordination octahedron; each Cu(2) ion is similarly coordinated by four OH at 1.989, 1.997, 2.009 and 2.018 Å, one OH at 2.309 Å, and one O at 2.384 Å. The structure involves layers of such deformed octahedra, of theC6-type, linked together by hydrogen bonds through the NO3 ions. Similarities to and differences from the structure of the monoclinic polymorphous form are discussed. 相似文献
20.
Huating Chen Dongsheng Deng Shaobin Miao Baoming Ji 《Crystal Research and Technology》2008,43(7):786-790
A seven‐coordinate Mn(II) complex of N,N,N ′,N ′‐tetrakis[(2‐benzimidazolyl)methyl]‐1,2‐cyclohexanediamine ( CDTB ), namely, [Mn(CDTB)(DMF)](Pic)2·C2H5OH was synthesized and characterized by elemental analyses, IR spectra and X‐ray single‐crystal diffraction. The complex crystallizes in a typical hybrid organic‐inorganic pattern. The crystal belongs to the monoclinic system, space group P 2 (1) / n with cell constants a = 13.3343(6) Å, b = 33.7015(16) Å, c = 13.7286(6) Å, β = 108.9990(10)°, Z = 4. The structure was solved by direct methods and refined to R = 0.0561 (wR2 = 0.1172). The structure analysis reveals that the Mn(II) has a capped octahedron geometry with seven‐coordination mode, furthermore, the [Mn(CDTB)(DMF)]2+ building blocks were extended into well‐ordered supramolecular networks by complementary hydrogen bonds, and the linkers of the ethanol molecules and the picrate anions play an important role in the self‐assembly process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献