Solubility of iron(Ⅲ) and nickel(Ⅱ) acetylacetonates in supercritical carbon dioxide

As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of nanocomposites.Recently,metal acetylacetonates have shown great potential for the preparation of single-atom catalytic materials.In this study,the solubilities of iron(Ⅲ)acetylacetonate(Fe(acac)3)and nickel(Ⅱ)acetylacetonate(Ni(acac)2)were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility data.Solubility was measured using a static weight loss method.The semi-empirical models proposed by Chrastil and Sung et al.were used to correlate the solubility data of Fe(acac)3 and Ni(acac)2.The equations obtained can be used to predict the solubility of the same system in the experimental range.

Acetylacetone-TiO_(2) Promoted Large Area Compatible Cascade Electron Transport Bilayer for Efficient Perovskite Solar Cells

In designing efficient perovskite solar cells(PSCs),the selection of suitable electron transport layers(ETLs)is critical to the final device performance as they determine the driving force for selective charge extraction.SnO_(2)nanoparticles(NPs)based ETLs have been a popular choice for PSCs due to superior electron mobility,but their relatively deep-lying conduction band energy levels(ECB)result in substantial potential loss.Meanwhile,TiO_(2)NPs establish favorable band alignment owing to shallower ECB,but their low intrinsic mobility and abundant surface trap sites impede the final performance.For this reason,constructing a cascaded bilayer ETL is highly desirable for efficient PSCs,as it can rearrange energy levels and exploit on advantages of an individual ETL.In this study,we prepare SnO_(2)NPs and acetylacetone-modified TiO_(2)(Acac-TiO_(2))NPs and implement them as bilayer SnO_(2)/Acac-TiO_(2)(BST)ETL,to assemble cascaded energy band structure.SnO_(2)contributes to rapid charge carrier transport from high electron mobility while Acac-TiO_(2)minimizes band-offset and effectively suppresses interfacial recombination.Accordingly,the optimized BST ETL generates synergistic influence and delivers power conversion efficiency(PCE)as high as 23.14%with open-circuit voltage(V_(oc))reaching 1.14 V.Furthermore,the BST ETL is transferred to a large scale and the corresponding mini module demonstrates peak performance of 18.39%PCE from 25 cm^(2)aperture area.Finally,the BST-based mini module exhibit excellent stability,maintaining 83.1%of its initial efficiency after 1000 h under simultaneous 1 Sun light-soaking and damp heat(85℃/RH 85%)environment.

Study on Dihydrated Praseodymium Acetylacetonate by Photoacoustic Spectra with Broad Wavelength Range

The UV Vis, NIR and MIR photoacoustic spectra of Pr(aa) 3·2H 2O were measured and most f f transition peaks of Pr 3+ are detected. The peak split and peak shift are studied also. The covalency parameter is calculated and it turns out that the covalent bonds between Pr(Ⅲ) ions and ligands exist. The results conclude that photoacoustic spectroscopy offers a unique and complementary method in analysis of solid rare earth complexes. Compared with conventional FT IR transmission and absorption approaches, PAS has the advantages of fast, nondestructive analysis and high resolution.

Electrodeposition of aluminium and aluminium-copper alloys from a room temperature ionic liquid electrolyte containing aluminium chloride and triethylamine hydrochloride

The electrodeposition of A1 and A1-Cu binary alloys on to gold substrates from a room temperature ionic liquid electrolyte containing A1C13-EtaNHC1 was studied. The electrochemical behavior of the electrolyte and the mechanism of deposition were investigated through cyclic voltammetry （CV）, and the properties of deposits obtained were assessed by scanning electron microscopy with energy dispersive X-ray spectroscopy （SEM-EDS） and X-ray diffraction （XRD）. A1 of 70μm in thickness and an A1-Cu alloy of 30μm in thickness with 8at% copper were deposited from the electrolyte. SEM images of the deposits indicate that the A1 deposit was smooth and uniform, whereas the Al-Cu deposit was nodular. The average crystalline size, as determined by XRD patterns, was found to be （30±5） and （29±5） nm, respectively, for A1 and A1-Cu alloys. Potentiodynamic polarization （Tafel plots） and electrochemical impedance spectroscopic （EIS） measurements showed that Al-Cu alloys are more corrosion resistant than Al.

Preparation of Rod-like Aluminum Doped Zinc Oxide Powders by Sol-gel Technique Using Metal Chlorides and Acetylacetone Precursors

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

Enhancement and Optimization of ATO Nano-crystalline Films Properties by the Addition of Acetylacetone as Modifier in the Sol-gel Process

Sb-doped Sn O2(ATO) thin films have been prepared using the spin coating method by selecting the proper amount of acetylacetone as solution modifier. All ATO powders and films exhibited the cassiterite rutile-like structure in a crystal size below 10 nm under all the experimental conditions and a nonpreviously reported crystal structure was observed at high acetylacetone loads. The acetylacetone molar ratio influenced notably the optical and electrical properties of ATO films. When prepared at an acetylacetone molar ratio of 4, ATO films exhibited optical transparencies above 90% in the visible region and above 40% in the UV region for thicknesses of 100 and 300 nm. Films in a thickness of 100 nm and at an annealing temperature of 650 ℃ accounted for a high transparency of 97% in the visible wavelength. Films prepared at an acetylacetone molar ratio of 4 exhibited an electric resistivity of 1.33×10-3 Ω·cm at an annealing temperature of 650 ℃. The optimal Sb content for ATO films was found to be 8 at%. The relationships among the properties of starting solutions, the experimental parameters, and properties of ATO films are discussed.

Synthesis,spectroscopic characterization and thermal studies of some lanthanide(Ⅲ) nitrate complexes with a hydrazo derivative of 4-aminoantipyrine

A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), or Gd(Ⅲ) and HAAP=3-{[2-(N-1-phenyl-2,3-dimethylpyrazol-3-in-5-on-4-yl)]hydrazone}pent-2,3,4-trione. The ligand and metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, infrared, far infrared and proton NMR spectral data. The spectral data revealed that the ligand existed in the hydrazo form and coordinated to the metal ion without deprotonation in a neutral tridentate manner, through carbonyl oxygen of pyrazolone ring, hydrazo nitrogen and carbonyl oxygen of the acetylace-tone moiety. The molar conductance values adequately supported their non-electrolytic nature. The ligand and the praseodymium(Ⅲ) complex were subjected to X-ray diffraction studies. Thermal decomposition behavior of the lanthanum(Ⅲ) complex was also examined.

Synthesis, Crystal Structure and Thermal Stability of (Diacetylacetone)(diimidazole)Nickel(II) Complex

The title compound, [Ni(acac)2(Im)2] (acac = acetylacetone), has been obtained by the reaction of Ni(acac)2 with imidazole ligand in the ethanol solvent. The blue crystal is of triclinic, space group Pi with a = 7.472(2), b = 9.456(2), c = 13.823(3) ? a = 85.55(3), = 89.03(3), ? = 80.63(3)o, C16H22N4NiO4, Mr = 393.09, V = 960.7(3) 3, Z = 2, Dc = 1.359 g/cm3, F(000) = 412, = 1.036 mm-1, R = 0.0549 and wR = 0.1615. The crystal structure consists of two disconnected structural units. Each Ni atom coordinated by two N atoms from two imidazole ligands and four O atoms from two acetylactone ligands adopts a slightly distorted octahedron. The structure characterization was performed by means of IR, UV, TG, elemental analysis and single-crystal X-ray analysis. The thermal gravity (TG) data indicate that thermal decomposition of the title compound takes place in two steps, and the residue is NiO.

Synthesis and Crystal Structure of Zn(Ⅱ) Complex with 2-Aminopyridine and Acetylacetone

A mixed complex [Zn（C5H6N2）（HL）2] （C5H6N2 = 2-aminopyridine, H2L = acetylacetone） has been synthesized and characterized by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 7.4490（15）, b = 8.2650（17）, c = 27.615（6） A°, β= 101.69（3）°, V = 1664.9（6）A°^3, Z = 4, Mr = 357.70, Dc = 1.427 g/cm^3, F（000） = 744, μ = 1.493 mm^-1, R = 0.0309 and wR = 0.0771. The Zn（Ⅱ） is coordinated by one nitrogen atom from 2-aminopyridine and four oxygen atoms from two acetylacetone anions to furnish a distorted square pyramid geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds.

Transport of Indium, Gallium and Thallium Metal Ions Through Chromatographic Fiber Supported Solid Membrane in Acetylacetone Containing Mixed Solvents

The transport of metal ions of indium, gallium and thallium from source solution to receiving phase through the chromatographic fiber supported solid membrane in the acetylacetone （HAA） containing mixed solvent system has been explored. The fibers supported solid membranes were prepared with chemical synthesis from cellulose fibers and citric acid with the carboxylic acid ion exchange groups introduced. The experimental variables, such as concentration of metal ions （10^-2 to 10^-4 mol.L^-1） in the source solution, mixed solvent composition [for exampl, e, acetylacetone, （2,4-pentanedione）, （HAA） 20% （by volume）, 1,4-dioxane 10% to 60% and HC1 0.25 to 2 mol.L^-1] in the receiving phase and stirring speed （50-130 r.min ） of the bulk source and receiving phase, were explored. The efficiency of mixed solvents for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane was evaluated. The combined ion exchange solvent extraction （CIESE） was observed effective for the selective transport of thallium, indium and gallium metal ions through fiber supported solid membrane in mixed solvents. The oxonium salt formation in the receiving phase enhances thallium, indium and gallium metal ion transport through solid membrane phase. The selective transport of thallium metal ions from source phase was observed from indium and gallium metal ions in the presence of hydrochloric acid in organic solvents in receiving phase. The separation of thallium metal ions from the binary mixtures of Be（II）, Ti（IV）, AI（III） Ca（II）, Mg（II）, K （I）, La（III） and Y（III） was carried out in the mixed solvent system using cellulose fiber supported solid membrane.

AROMATIC AND HETEROCYCLIC NITRILES AND THEIR POLYMERS ⅩⅧ. THE POLYMERIZATION KINETICS OF BENZONITRILE CATALYZED BY METAL ACETYLACETONATE

The bulk polymerization of benzonitrile catalyzed by Co(Ⅱ), Co(Ⅲ) and Fe(Ⅲ) acetylacetonate was studied. The results of kinetics study show that the rate of polymerization was proportional to first power of the concentration of catalyst and second power of the concentration of monomer.

UV Spectral Analysis of the Chemical Modification and Photolysis of Acetylacetone Modified Alumina Aqueous Solution

Acetylacetone was firstly introduced into the aqueous media with the presence of aluminum sec-butoxide and pep-tizator. It was confirmed that the UV (ultraviolet) absorption band of acetylacetone underwent 14 nm of red-shift due to the formation of the six-membered ring of the complex between alumina and acetylacetone in the aqueous solution. It was also found that the chemical modification can be dissociated by the UV irradiation with a wavelength shorter than 286 nm as a result of the excitation of π-π* transition in the complex.

Synthesis, Structure and Electrochemistry of Macrocyclic 1,1'-Bis(1,3-phenyleneoxyacetylpyrazoyl)ferrocene

1,1＇-Diacetoacetylferrocene 1 reacted with phenylene-1,3-dioxyactyl hydrazine 2 in absolute ethanol to give the macrocyclic ferrocenyl dipyrazole compound in moderate yield. Determined by X-ray structure analysis, it crystallizes in monoclinic system, space group P21/c with a = 13.7509（4）, b = 8.1277（2）, c = 21.7472（6） A, β = 103.1030（10）°, V = 2367.25（11） A^3, Z = 4, Dc = 1.505 g/cm^3, R = 0.0353 and wR = 0.0811. The electrochemical studies reveal that redox of Fe^＋/Fe in ferrocene is a reversible one-electron process.

A facile electrochemical synthesis of caffeic acid derivatives in the presence of acetylacetone or methyl acetoacetate in aqueous medium

The anodic oxidation of caffeic acid in the presence of acetylacetone or methyl acetoacetate in aqueous solution has been studied by cyclic voltammetry and controlled-potential electrolysis techniques. The result showed that caffeic acid was oxidized to the corresponding o-benzoquinone, which underwent further Michael-addition with acetylacetone or methyl acetoacetate to produce caffeic acid derivative 3,4-dihydroxy-6-(1-acetylacetone)-yl cinnamic acid 4a or 3,4-dihydroxy-6-(1-acetyl-methylacetate)-yl cinnamic acid 4b.

Intradiffusion, density and viscosity studies in binary liquid systems of acetylacetone + DMF/DMSO/benzene at 303.15 K and 333.15 K

Intradiffusion coefficients of acetylacetone(AcAc) and DMF/DMSO/benzene in binary systems over the entire concentration range at 303.15 K were determined by 1H diffusion-order spectroscopy(DOSY) nuclear magnetic resonance(NMR) method based pulse field gradient(PFG).The densities and viscosities of the above three binary systems at 303.15 K were also studied and employed to calculate the excess molar volumes(V^E) and deviations in viscosity(△η).Besides,experiments were carried out at 333.15 K for the system of AcAc+DMF.The solvent and temperature effect upon the difference in D between enol and keto tautomers,the tautomeric equilibrium and excess properties(V^E and △η) were discussed as well.Isotherms of V^E as a function of mole fraction of AcAc(χ_1) show positive deviations in benzene but negative deviations in DMF and DMSO,whereas isotherms of △ηas a function of χ_1 record positive deviations in DMF but negative in benzene and DMSO.V^E values show more negative and △η values are less positive in the system of AcAc+DMF at 333.15 K compared to 303.15 K.The V^E and △η were fitted to a Redlich-Kister type equation and the measured results were interpreted concerning molecular interactions in the solutions.

AROMATIC AND HETEROCYCLIC NITRILES AND THEIR POLYMERS XIX:THE POLYMERIZATION OF SUBSTITUTED BENZONITRILES CATALYZED BY COBALTIC ACETYLACETONATE

The polymerization kinetics of 4, 4'-biphenyldicarbonitrile and other substituted ben-zonitriles catalyzed by cobaltic acetylacetonate was studied. The structure of polymer ofdifferent substituted benzonitrile was also determined. It is found that the rate of polymeri-zation and the structure of polymer is greatly affected by the substituent of benzonitriles.

COMPLEX OF MESO-TETRA-(1-NAPHTHYL)TETRABENZOPORPHYRIN WITH HOLMIUM ACETYLACETONATE

Complex of meso-tetra-(1-naphthyl)tetrabenzo-porphyrin with holmium acetylacetonate,Ho(TNTBP)acac(TNTBP:meso-tetra-(1-naphthyl) tetrabenzoporphyrin.Hacac:acetylacetone)have been prepared and char- acterized by elemental analyses,ultra-violet visible spectra and in- frared spectra.

STUDIES ON THE INITIATION MECHANISM OF CERIC ION AND ACETYLACETONE REDOX SYSTEM IN VINYL POLYMERIZATION

The initiation mechanism of acrylamide (AAM)polymerization using ceric ion/acetylacetone system as an initiator has been studied. The redox polymerization was revealed by the low value of overall activation energy of AAm polymerization. The structure of free radicals formed from above-mentioned initiation sytem were detected by radical trapping and ESR spectra techniques and the end groups of polymers obtained were determined by FT-IR spectra analysis method. Based on these results the initiation mechanism is proposed.