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1.
Mesoporous ZnO nanosheets were successfully prepared by pyrolytic transformation of zinc carbonate hydroxide hydrate, Zn4CO3(OH)6·H2O. The nanosheets were initially formed as assemblies on glass substrates during chemical bath deposition (CBD) in aqueous solutions of urea and zinc acetate dihydrate, zinc chloride, zinc nitrate hexahydrate, or zinc sulfate heptahydrate at 80°C. It was key to induce heterogeneous nucleation of Zn4CO3(OH)6·H2O by promoting a gradual hydrolysis reaction of urea and controlling the degree of supersaturation of zinc hydroxide species. Morphology of Zn4CO3(OH)6·H2O was largely influenced by the anions present in the CBD solutions. The Zn4CO3(OH)6·H2O nanosheets were transformed into wurtzite ZnO by heating at 300°C in air without losing the microstructural feature.  相似文献   

2.
The standard enthalpies of reaction of four zinc hydroxide nitrates Zn(OH)(NO3)-H2O, Zn3(OH)4(NO3)2, Zn5(OH)8(NO3)2·2H2O et Zn5(OH)8(NO3)2 and zinc oxide with a solution of nitric acid (2N) were measured in a solution calorimeter. These results, combined with auxiliary thermochemical values from the literature, yielded values of ?429.34, ?442.41, ?897.41 and ?750.70 kcal mol?1 respectively, for the molar enthalpies of formation of these zinc hydroxide nitrates.  相似文献   

3.
    
A mixed-metal hydroxysalt of formula Cu1.6Zn0.4(OH)3(OAc)·H2O has been synthesized by an acetate hydrolysis route. Acetate ions can be exchanged with simple inorganic anions such as chloride and nitrate, and organic anions such as benzoate and large surfactant anions such as dodecyl sulphate. Structures of these hydroxysalts are derived from that of Cu2(OH)3NO3·H2O with some of the Cu2+ ions being replaced by Zn2+.  相似文献   

4.
Simonkolleite is a zinc-layered hydroxide salt with the formula Zn5(OH)8Cl2·H2O. It has a platelet morphology and can be used for many applications, owing to both its layered structure and its nature as a hydroxide salt. It can be prepared via a simple precipitation from ZnCl2 and NaOH in water thermostated at 50 °C. Depending on the synthesis conditions, we could obtain different sizes and a hybrid containing parts of ZnO. We studied the influence of the OH:Zn molar ratio, the addition order, and the maturation time after the reaction was completed. With the support of pH profiles, kinetic studies, and thermodynamic equilibrium data, we were able to propose a global synthesis mechanism explaining the influence of those three parameters and identify the range of conditions in which simonkolleite can be formed. Depending on the desired application, we were able to synthesize bigger or smaller layered crystals of simonkolleite, in the presence of absence of ZnO.  相似文献   

5.
Three new Schiff base ligands N-(3-formyl-5-methylsalicylidene)-2-aminoethanol (H2L1), N-(3-hydroxylmethyl-5-methylsalicylidene)-2-aminoethanol (H3L2), 2,6-bis(o-carboxyphenyliminomethene)-4-methylphenol (H3L3) and their binuclear ZnII complexes [Zn2(HL1)2]Cl2 · 2H2O (ZnHL1), [Zn2(H2L2)2]Cl2 · H2O (ZnH2L2) and [Zn2(HL3)Cl2] · H2O (ZnHL3) were synthesized and characterized by 1H-NMR, elemental analysis, IR and molar conductivity. The results suggest, in every case, two Zn2+ ions were bridged by phenolic OH group oxygen, forming a binuclear complex. The binding properties of these complexes to calf thymus DNA (ct-DNA) were investigated. Absorption and fluorescence spectra are together suggestive that both ZnHL1 and ZnHL3 interact with ct-DNA through intercalative mode, while ZnH2L2 interact with ct-DNA by non-intercalative interaction. Moreover, ZnHL3 can bind to ct-DNA more strongly than ZnHL1. These complexes also exhibited good scavenging activity on the hydroxyl radical (•OH), which are better than those of their corresponding ligands.  相似文献   

6.
Zinc hydroxide chloride particles were synthesized by hydrolysis of ZnCl2 solutions dissolving AlCl3 at different atomic Al/Zn ratios from 0 to 1.0 and characterized by various techniques. Increasing Al/Zn ratio changed the crystal phases of the products as ZnO→ZnO+ZHC (Zn5(OH)8Cl2·H2O)→ZHC→LDH (layered double hydroxides, Zn-Al-Cl) and the particle morphology as agglomerates (ZnO)→fine particles (ZnO)→plates (ZHC)+rods (ZnO)→plates (ZHC)→plates (LDH). The atomic Cl/Zn ratios of LDH particles formed at Al/Zn?0.3 were ca. 0.3 despite the increase of Al/Zn ratio, being due to the intercalation of CO32− into the LDH crystal. The OH content of LDH estimated by TG was reduced by the deprotonation of OH to counteract the excess positive charge produced by replacing Zn(II) with Al(III). ZHC exhibited a high adsorption selectivity of H2O.  相似文献   

7.
The reaction scheme of thermal decomposition for four zinc hydroxynitrates was investigated by means of differential scanning calorimetry, thermogravimetry, mass spectrometry, and radiocrystallography. The thermal transformation of Zn(OH)(NO3) · H2O and of Zn3(OH)4(NO3)2 involves the formation of gaseous water and nitric acid from an actual chemical reaction. This reaction is not observed for Zn5(OH)8(NO3)2 · 2H2O and Zn5(OH)8(NO3)2. These results show that the formation of gaseous nitric acid molecules inside the solids is specific to hydroxynitrates of divalent metals M, whose lamellar crystalline structure is characterized by a stacking of hexagonal close-packed layers of formula MX2+m, where m = 0 or 1 and X = OH?, H2O, or NO?3.  相似文献   

8.
New octahedral anionic heterometal rhenium-osmium cluster complexes [Re5OsSe8(OH)6]3− and [Re4Os2Se8(OH)6]2− were synthesized starting from [Re5OsSe8Cl6]3− and [Re4Os2Se8Cl6]2−, respectively. They were isolated as salts of the compositions Cs3[Re5OsSe8(OH)6] · 11H2O (I), K3[Re5OsSe8(OH)6] · 7H2O (II), and K2[Re4Os2Se8(OH)6] · 3H2O (III). The protonation of the terminal OH ligands of [Re5OsSe8(OH)6]3− in an aqueous solution resulted in crystallization of a neutral complex [Re5OsSe8(H2O)3(OH)3] · 12H2O (IV). The compounds have been characterized by single-crystal X-ray diffraction analysis. The luminescence properties of [Re5OsSe8(OH)6]3− and [Re4Os2Se8(OH)6]2− were studied. In addition, the electronic structures of the complexes were elucidated by DFT calculations.  相似文献   

9.
Reactions of the rigid–flexible N-heterocycle 1,3-bis(5-(pyridine-2-yl)-1,2,4-triazole-3-yl) propane (H2L) with MCl2 (M = Fe, Co, Cu or Zn) gave coordination complexes, {[Fe 2 III Cl4(H2L)2]·2Cl}·EtOH·H2O (1), {[Co3Cl5(HL)]·H2O} n (2), {[Co4Cl4(H2L)2(H2O)4]·[CoCl4]2}·H2O (3), [Cu2Cl3(HL)(H2O)]6·5H2O (4), [Cu 2 II CuICl4(HL)] n (5), {[Zn2Cl2(L)H2O]·H2O} n (6) and [Zn4Cl6(HL)2] (7), which have been characterized by single-crystal X-ray diffraction. Structural analysis reveals that the pyridine triazole ligand attains versatile coordination modes in these complexes. Complexes 1, 3, 4 and 7 consist of 0D clusters with binuclear or tetranuclear units; complex 2 presents a 2D network accompanied by HL? and chloride bridges; complexes 5 and 6 show 1D chains with [Cu3] and [Zn2] subunits. In addition, the electrospray ionization mass spectrometry properties of selected complexes were investigated, revealing the stabilities and structural states of these complexes in solution. These results indicate that H2L is an excellent multiconnection linker for the construction of diverse coordination complexes.  相似文献   

10.
Seven new bi‐ and polyhomonuclear transition metal complexes with three polyhydroxlated bisazodianil ligands were synthesized and characterized. The ligands were derived from condensation of 6‐(5‐formyl‐2‐hydroxyphenylazo)‐2,4‐dihydroxypyrimidine with aliphatic diamines (H8L1, H8L2 and H6L3). The data of elemental and thermal analyses, molar conductance measurement, IR, electronic and ESR spectra as well as magnetic moment measurements support the formation of [L1Co7Cl6(H2O)10]·22H2O ( 1 ), [H2L2Mn6Cl6(H2O)8]·3H2O·2EtOH ( 3 ), [L2Co8Cl8(H2O)12]·24H2O ( 4 ), [H4L3Co2Cl2(H2O)2]·8H2O·2EtOH ( 6 ) with a tetrahedral geometry and [H2L1Ni5Cl4(H2O)16]·19H2O·EtOH ( 2 ), [L2Ni8Cl8(H2O)28]·8H2O·EtOH ( 5 ) with an octahedral geometry while [H6L3Cu3(H2O)7]Cl3·10H2O ( 7 ) has a distorted tetrahedral arrangement. The mode of bonding between the metal ions and the ligand molecules is determined and the metal‐metal interaction was studied. The activation thermo‐kinetic parameters for the thermal decomposition steps of the complexes E*, ΔH*, ΔS*, and ΔG* were calculated.  相似文献   

11.
The steps associated with the thermal decomposition of Zn5(OH)8(NO3)2·2H2O and ZnOHNO3·H2O are re-examined. Previous reports have suggested that Zn5(OH)8(NO3)2·2H2O decomposes to ZnO via two intermediates, Zn5(OH)8(NO3)2 and Zn3(OH)4(NO3)2 whereas ZnOHNO3·H2O has been reported to decompose to ZnO via a Zn3(OH)4(NO3)2 intermediate. In this study, we demonstrate using TG, mass spectral analysis of evolved gases and in situ variable temperature powder X-ray diffraction analysis that, in fact, in the decomposition of Zn5(OH)8(NO3)2·2H2O an anhydrous zinc nitrate intermediate is also involved. We, additionally, show that the decomposition of ZnOHNO3·H2O to ZnO also involves the formation of an anhydrous zinc nitrate intermediate. The anhydrous zinc nitrate formed in both cases is poorly crystallised and this observation may explain why this phase could not be observed by PXRD analysis in the previous studies.  相似文献   

12.
The Ce,Mn mixed-metal polynuclear compounds [Ce 3Mn6(O)5(OH)3Piv12Cl2(THF)3]·2THF, [Ce3Mn8(O)8Piv16Cl2(HPiv)2]·C7H16, [Ce10Mn4(O)6(OH)12Piv16Cl2(THF)2]·2THF·2H2O, [CeMn11Cl3(O)8Piv15(H2O)]·CH2Cl2, and [CeMn8(O)8Piv12(HPiv)2(THF)2] were prepared and structurally characterized. The possibility of synthesizing p,d,f-heterospin complexes by replacing coordinated THF molecules by nitroxide molecules was exemplified by the reaction of [Ce3Mn6(O)5(OH)3Piv12Cl2(THF)3]·2THF with nitronyl nitroxides (NIT-R is 2-R-4,4,5,5-tetramethyl-24midazoline-l-oxyl 3-oxide; R is Me or 4-Py). The X-ray diffraction study of these complexes showed that [Ce3Mn6(O)5(OH)3Piv12Cl2(HPiv)(NIT-Me)2] and [CeMn8(O)8Piv12(NIT4-Py) 4] · 2C6H14 have a molecular structure and [Ce3Mn6(O)5(OH)3-Piv12Cl2(NIT-Me)(H2O)] is an infinite chain.  相似文献   

13.
Naphthaldimines containing N2O2 donor centers react with platinum(II) and (IV) chlorides to give two types of complexes depending on the valence of the platinum ion. For [Pt(II)], the ligand is neutral, [(H2L1)PtCl2]·3H2O (1) and [(H2L3)2Pt2Cl4]·5H2O (3), or monobasic [(HL2)2Pt2Cl2]·2H2O (2) and [(HL4)2Pt]·2H2O (4). These complexes are all diamagnetic having square-planar geometry. For [Pt(IV)], the ligand is dibasic, [(L1)Pt2Cl4(OH)2]·2H2O (5), [(L2)Pt3Cl10]·3H2O (6), [(L3)Pt2Cl4(OH)2]·C2H5OH (7) and [(L4)Pt2Cl6]·H2O (8). The Pt(IV) complexes are diamagnetic and exhibit octahedral configuration around the platinum ion. The complexes were characterized by elemental analysis, UV-Vis and IR spectra, electrical conductivity and thermal analyses (DTA and TGA). The molar conductances in DMF solutions indicate that the complexes are non-ionic. The complexes were tested for their catalytic activities towards cathodic reduction of oxygen.  相似文献   

14.
Samples of β-Co2(OH)3Cl and Zn5(OH)8Cl2 · H2O have been prepared and their thermal decomposition studied in air and N2 by DTA and TG up to 1000°C. X-Ray diffraction analysis of the thermal treatment products in air at various temperatures from 100 to 100°C was also carried out. The results obtained made it possible to establish the steps through which the pyrolysis of both compounds proceeds.  相似文献   

15.
Some new complexes of rhenium containing monocoordinating acetylacetone viz. [Re(NO)(acac)2(Cl)H2O], Re(NO)(acac)3(acacH)(H2O)2 have been synthesized by reacting acetylacetone with either Re(NO)Cl3 · H2O or Re(NO)(OH)3 · H2O. The preparation of [Re(NO)(py)(acac)2(Cl) · H2O], [Re(NO)(acac)(OH)(Cl) · H2O], [Re2(NO)2(acacH)3(acac)2 · Cl4], [Re(NO)(acac)2(OH) · H2O] · 2 H2O have also been described. These complexes were characterized through their elemental analyses, u.v., vis, i.r., 1Hn.m.r., magnetic, and conductance data.  相似文献   

16.
The compounds [Ni(H2O)2(En)2][{Ni(En)2}Re6S8(OH)6] · 7H2O (I), [{Cu(En)2}Re6S8(H2O)2(OH)4] · 4H2O (II), and [Ni(H2O)2(En)2]0.5[Re6Se8(H2O)3(OH)3] · 10H2O (III) were synthesized by layering aqueous solutions of Ni(En)2Cl2 or Cu(En)2Cl2 (En is ethylenediamine) onto aqueous solutions of the potassium salts of the corresponding octahedral chalcohydroxo rhenium cluster complexes [Re6Q8(OH)6]4− (Q = S, Se). The structure of the obtained compounds was determined by X-ray diffraction analysis.  相似文献   

17.
Coordination polymers (CPs) with specific structures and functional luminescence have been widely designed as sensors for detecting small molecules and ions. In this study, with or without the help of an N‐donor auxiliary linker, three new ZnII CPs, namely, three‐dimensional (3D) poly[[pentaaquabis[μ3‐5‐(4‐carboxybenzyloxy)isophthalato]bis[μ6‐5‐(4‐carboxylatobenzyloxy)isophthalato]di‐μ3‐hydroxido‐hexazinc(II)] trihydrate], {[Zn6(C16H10O7)2(C16H9O7)2(OH)2(H2O)5]·3H2O}n or {[Zn63‐HL)26L)23‐OH)2(H2O)5]·3H2O}n, ( I ), one‐dimensional (1D) catena‐poly[[[aqua(1,10‐phenanthroline)zinc(II)]‐μ2‐5‐(4‐carboxybenzyloxy)isophthalato] dihydrate], {[Zn(C16H10O7)(C12H8N2)(H2O)]·2H2O}n or {[Zn(μ2‐HL)(phen)(H2O)]·2H2O}n (phen is 1,10‐phenanthroline), ( II ), and 3D poly[diaquatetrakis(4,4′‐bipyridine)bis[μ6‐5‐(4‐carboxylatobenzyloxy)isophthalato]di‐μ3‐formato‐di‐μ3‐hydroxido‐pentazinc(II)], [Zn5(C16H9O7)2(HCOO)2(OH)2(C10H8N2)4(H2O)2]n or [Zn54L)2(bpy)42‐OH)23‐HCOO)2(H2O)2]n (bpy is 4,4′‐bipyridine), ( III ), have been constructed from the semi‐rigid tricarboxylic acid 5‐(4‐carboxybenzyloxy)isophthalic acid (H3L) under hydrothermal conditions. CP ( I ) exhibits a twofold interpenetrated 3D+3D→3D skeleton with a 3 , 5 ‐conn topology constructed from triangular trinuclear [Zn3(COO)43‐OH)] clusters, in which the H3L ligand adopts three different coordination modes. CP ( II ) exhibits a 1D infinite chain and stacking that gives a 3D structure mediated by hydrogen bonds and weak interactions. CP ( III ) is an interesting 3D 3 , 4 , 8 ‐conn network including linear tetranuclear [Zn42‐OH)2(HCOO)2(COO)2] clusters with a new {4·62}2{4·64·8}{46·619·83} topological symbol. The influences of the flexible –CH2–O– linker of the H3L ligand and subtle environmental factors, such as solvent, pH value and auxiliary ligands, on the formation of the final structures are also discussed. The solid‐state fluorescence spectra of CPs ( I )–( III ) were recorded at room temperature and all show better fluorescence performances than H3L. In particular, ( II ) can act as a potential multifunctional fluorescent material for sensing hexavalent chromium ions in aqueous solution with high stability, selectivity and sensitivity. Under ultraviolet light of 365 nm from a UV lamp, a signal response of fluorescence from turning on to off can be observed with the naked eye. It was found that the detection for hexavalent chromium (i.e. Cr2O72?) by ( II ) has a high selectivity [KSV = 1.61 × 104M?1 and limit of detection (LOD) = 0.434 µM] in aqueous solution. Quenching mechanisms were also studied in detail.  相似文献   

18.
Some Reactions with [Mo6Cl8]Cl4 The reaction of [Mo6Cl8]Cl4 with different chemical agents has been investigated: The methoxylation depends on the CH3O? concentration in CH3OH. The reaction with HF leads to a partial fluorinated [Mo6Cl8] product. With NH4F (NH4)2[Mo6Cl8]F6 in formed, the hydrolysis of which leads to [Mo6Cl8]F3(OH) · 2.5 H2O. This compound can be decomposed thermically into [Mo6Cl8]O2. [Mo6Br8]F62? on hydrolysis leads to [Mo6Br8]F3(OH) · 5 H2O. With CsF Cs2[Mo6Cl8]F6 is formed, which by hydrolysis is transformed into [Mo6Cl8]F3(OH) · 2.5 H2O and possibly to [Mo6Cl8]F4 · xH2O(?). In reaction of [Mo6Cl8]Cl4 with H2SO4 one gets [Mo6Cl8](SO4)2. Salts e. g. [(C6H5)4As]2[Mo6Cl8](OC6F5)6 and adducts e. g. [Mo6Cl8](OC6F5)4 · 2 HMPA are prepared. The compounds have been characterized by X-ray powder-diagramms and by IR-spectra.  相似文献   

19.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

20.
The coordinating properties of a new bis(pyridylhydrazone) ligand derived from iminodiacetic acid diethyl ester and 2-pyridinecarboxaldehyde (picolinaldehyde) H3Imdp and of the bis(salicylhydrazone) H5Imds and H4MeImds ligands derived, respectively, from iminodiacetic acid diethyl ester and from methyl-iminodiacetic acid diethyl ester and salicylaldehyde were considered, by means of analytical and spectroscopic methods, towards first row transition metal ions. These ligands showed various coordination modes in complexation with Cu(II), Co(II), Mn(II) and Zn(II) ions. In particular, we have synthesized and characterized, by analytical, 1H NMR and IR techniques, tri-, di- and mononuclear metal complexes of formula Co3(HImdp)(NO3)4·2H2O, Cu3(HImdp)(NO3)4·C2H5OH·H2O, Cu3(HImdp)Cl4, Zn2(H3Imdp)(ClO4)4·2H2O, Co3(HImds)Cl2·CH3OH·H2O, Zn2(H3Imds)Cl2·2H2O, Co(H4Imds)NO3·2H2O, Mn(H4Imds)Cl·CH3OH·H2O, Cu(H3Imds)·CH3OH·H2O and Cu(H2MeImds).CH3OH·3H2O. Antibacterial, antifungal and antiprotozoal properties of H5Imds and H3Imdp together with three copper(II) trinuclear species of H5Imds of formula Cu3(HImds)(NO3)2.2CH3OH·2H2O, Cu3(HImds)(ClO4)2.EtOH·2H2O and Cu3(HImds)SO4·4H2O are also discussed. The H5Imds ligand and their trinuclear copper(II) complexes showed good activities versus Trichomonas vaginalis, Staphylococcus epidermidis and Acanthamoeba castellanii.  相似文献   

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