Solvothermal synthesis and adsorption performance of layered boehmite using aluminum chloride and high-alumina fly ash

High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization urgent.In this work,the alumina containing leaching solution obtained from Na_(2)CO_(3) roasting and HCl leaching of FAHAl was used as the mother liquor to prepare layered boehmite in situ.The preparation process with AlCl_(3) as the raw material was also compared.The formation process and mechanism of boehmite,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller method and adsorption experiments.Results showed that during the preparation of layered boehmite,the precursor Al(OH)_(3) from the reaction of Al^(3+) and OH-is transformed into boehmiteγ-AlOOH.The existence of ethanol is beneficial to regulate and promote the growth of boehmite crystal effectively.When water and ethanol are mixed with a volume ratio of 2:1 and used as the solvent,the maximum specific surface area of the boehmite is obtained at 135.7 m^(2)·g^(-1),and 99.16%of Congo red can be absorbed after 10 min when AlCl3 is used as a raw material.As purified leaching solution is used as the mother liquid,the crystallinity of boehmite decreases slightly when the pH value decreases from 12.5 to 11.When pH is 11,the removal efficiency of Congo red reaches a maximum of 72.25%.This process not only achieves the extraction of aluminum and high-value utilization of FAHAl but also provides a thought to prepare layered boehmite with adsorption properties.

Framework-solvent interactional mechanism and effect of NMP/DMF on solvothermal synthesis of [Zn_4O(BDC)_3]_8

In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.

Solvothermal synthesis and characterization of nanocrystalline vanadium-chromium composite oxides and catalytic ammoxidation of 2,6-dichlorotoluene

Vanadium‐chromium oxides(VCrO)were usually prepared by high‐temperature solid‐state reactions;however,mixed phases were frequently produced and the morphology of the products was not well controlled.In this work,we prepared amorphous VCrO precursors by using V2O5 and CrO3 and alcohols or mixtures of alcohol and water via solvothermal reaction at 180°C.The precursors were then calcined under nitrogen at various temperatures.The products were characterized by powder X‐ray diffraction,transmission electron microscopy,and X‐ray photoelectron spectroscopy.It was revealed that pure‐phase nanocrystalline orthorhombic CrVO4 was obtained when methanol or methanol/water was used as the solvothermal medium and the precursor was calcined at 700°C.The size of the CrVO4 crystals was around 500 nm when methanol was used,whereas it reduced significantly to less than 50 nm when a mixture of methanol and water was used.The sizes could be effectively tuned from 10 to 50 nm by varying the methanol/water volume ratio.To the best of our knowledge,this is the first report on the synthesis of pure‐phase CrVO4 nanocrystals.The nano‐CrVO4 showed almost the highest catalytic activity for the ammoxidation of 2,6‐dichlorotoluene to 2,6‐dichlorobenzonitrile among the reported bi‐component composite oxides,owing to its smaller particle size,larger specific surface area,and more exposed active centers.

Solvothermal synthesis of Co-substituted phosphomolybdate acid encapsulated in the UiO-66 framework for catalytic application in olefin epoxidation

Hybrid composites of phosphomolybdic acid@UiO-66(PMo12@UiO-66)and Co-substituted phosphomolybdic acid@UiO-66(PMo11Co@UiO-66)were synthesized using the direct solvothermal method.A variety of characterization results demonstrated that phosphomolybdic acid(PMo12)or Co-substituted phosphomolybdate acid(PMo11Co)clusters are uniformly dispersed in the cages of Zr-based metal-organic UiO-66 frameworks.The catalytic properties of these hybrid composites were investigated by applying the epoxidation of olefins with tert-butyl hydroperoxide as the oxidant.Compared to PMo12@UiO-66,PMo11Co@UiO-66 showed a much higher catalytic activity and was simply recovered by filtration and reused for at least ten runs without significant loss of catalytic activity.Particularly,PMo11Co@UiO-66 can efficiently convert cyclic olefins like limonenes to epoxides,and its selectivity to 1,2-limonene oxide reached 91%in the presence of a radical inhibitor such as hydroquinone.The excellent catalytic activity and stability of the hybrid composite PMo11Co@UiO-66 are mainly attributed to the uniform distribution of highly active PMo11Co units within the smaller cages of UiO-66,to the suitable surface polarity of the hybrid composite for facilitating the access of reagents and solvent,and to the strong interface-interactions between the polyoxometalate and the UiO-66 framework.

Solvothermal Synthesis and Characterization of HgTe Nanoplatelets Using Mercury(I) Source

Mercury telluride （HgTe） nanoplatelets were obtained via a facile solvothermal reaction of mercury（I） chloride and tellurium powder in ethylenediamine （en）. Mercury（I） was first applied as the mercury sources to prepare nanocrystal HgTe; moreover, the proposed mechanism for the fabrication of the sample was discussed in detail. The HgTe nanoplatelets were characterized by powder X-ray diffraction （PXRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM） and Fourier transform infrared spectroscopy （FT-IR）. The absence of IR absorption may render the title nanocrystal useful as an IR transparent material in the region.

Solvothermal Syntheses, Crystal Structures, Thermal Stability and Quantum Chemistry of Dinuclear Trialkyltin Complexes Constructed by Camphoric Acid

Two dinuclear organotin complexes C8H14（CO2SnCy3）2（1）（Cy = cyclohexyl group） and C8H14[CO2Sn（CH2CMe2Ph）3]2（2） were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri（2-methyl-2-phenyl）propyltin] oxide under solvothermal conditions, and these complexes were characterized by infrared spectra, elemental analyses, and H NMR spectra. The crystal of 1 belongs to the monoclinic system, space group P21/c with a = 1.83478（19）, b = 1.52707（18）, c = 1.9849（2） nm, β = 122.515（7）°, Z = 4, V = 4.6896（9） nm^3, Dc = 1.324 g/cm^3, μ（MoKα） = 1.103 mm^-1, F（000） = 1952, R = 0.0697 and wR = 0.2040. In addition, thermal stability and quantum chemical calculation of 1 were also studied.

Preparation of Copper Phthalocyanine Crystals Using Solvothermal Synthesis

A novel solvothermal synthesis method for the direct growth of B-form crystals of copper phthalocyanine（CuPc） is presented in this article. With quinoline as solvent, crystals were grown after cooling the reaction mixture of 1,3-diiminoisoindoline and copper oxide, heated for 9 h at 270 ℃, to room temperature in an autoclave. These high quality crystals were suitable for characterization measurements. The single-crystal diffraction data show a monoclinic system unit cell： a=1.4668（3） nm, b=0.48109（10） nm, c=1.9515（7） nm, a=90°, B=121.04（2）°, r=90°, where the corresponding cell volume is 1.17991 nm^3. Needle-like single crystals of CuPc up to 10.5 mm in length were obtained. The influences of different temperatures, reaction time and solvent volume on the crystal yields were also discussed. Optimum reaction conditions were 10 mL of quinoline, at 270 ℃ for 8 h.

Solvothermal Synthesis and Crystal Structure of a Layered Thioantimonate(Ⅲ) [C_4H_9NH_3]_2Sb_4S_7

An inorganic-organic hybrid thioantimonate（Ⅲ） [CH3（CH2）3NH3]2Sb4S7 1 with layered structure was synthesized by solvothermal method. 1 crystallizes in the triclinic system, space group P1 with a = 7.0124（11）, b = 11.919（2）, c =14.879（3）A, α = 108.791（3）, β= 102.441（3）, γ = 92.846（2）°, V= 1140.1（3）A3, Mr = 859.71, Z= 2, Do = 2.504 g/cm^3 ,μ = 5.324 mm^-1, F（000） = 804, S = 1.013, the Final R = 0.0297 and wR = 0.0618 for 3534 observed reflections with Ⅰ 〉 2 σ（Ⅰ）. 1 consists of [C4HgNH3]＋ cations and two-dimensional [Sb4ST]n^2n- anion which is composed of three SbS3 trigonal pyranaids and one SbS4 unit joined by sharing common comers. The anionic layers are stacked perpendicularly to the c axis of the unit cell forming two-dimensional channels between the layers. The [C4H9NH3]^＋ cations interdigitate in a bilayer and reside in the 2D channels leading to a sandwich-like arrangement of the anion and cations.

Solvothermal Synthesis and Characterization of (NH_3CH_2CH_2NH_3)HgSnS_4 with a Column Structure

A compound （NH3 CH2 CH2 NH3 ）HgSnS4 with a column structure was synthesized solvothermally and characterized by X-ray single-crystal diffraction. This compound crystallizes in the monoclinic space group C2/c with a = 1. 3863 （6） nm, b = 0. 6640 （ 3 ） nm, c = 2. 3198 （10） nm, β = 106. 168 （ 7 ）° and Z = 8. It consists of anionic columns of [ HgSnS4 ]^2- that are interrupted by cationic columns of [ EnH2 ]^2＋ . Its thermal and optical properties were studied.

Synthesis of Nickel Sulfide Particles by Solvothermal Process

Pyrite nickel disulfide and millerite nickel monosulfide have been successfully prepared by solvothermal method based on the reaction of Ni(NO3)2.6H2O and H2NC(S)NH2 in benzene and ethylenediamine (EDA). The final products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM). The effects of the solvent, reaction temperature and time on the morphology and phase of the products have been discussed.

Synthesis of the Complex Fluoride LiBaF_(3) through a Solvothermal Process

The complex fluoride LiBaF3 is solvothermally synthesized at 180degreesC and characterized by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. In the solvothermal process, the solvents, mole ratios of initial mixtures and reaction temperature play important roles in the growth of the single crystal.

Surfactant assisted solvothermal synthesis of LiFePO4 nanorods for lithium-ion batteries

Well-shaped and uniformly dispersed LiFePOnanorods with a length of 400–500 nm and a diameter of about 100 nm, are obtained with participation of a proper amount of anion surfactant sodium dodecyl sulfonate（SDS） without any further heating as a post-treatment. The surfactant acts as a self-assembling supermolecular template, which stimulated the crystallization of LiFePOand directed the nanoparticles growing into nanorods between bilayers of surfactant（BOS）. LiFePOnanorods with the reducing crystal size along the b axis shorten the diffusion distance of Liextraction/insertion, and thus improve the electrochemical properties of LiFePOnanorods. Such prepared LiFePOnanorods exhibited excellent specific capacity and high rate capability with discharge capacity of 151 mAh/g, 122 mAh/g and 95 mAh/g at 0.1C, 1 C and 5 C, respectively. Such excellent performance of LiFePOnanorods is supposed to be ascribed to the fast Lidiffusion velocity from reduced crystal size along the b axis and the well electrochemical conductivity. The structure, morphology and electrochemical performance of the samples were characterized by XRD, FE-SEM, HRTEM, charge/discharge tests, and EIS（electrochemical impedance spectra）.

Solvothermal synthesis and thermoelectric properties of skutterudite compound Fe_(0.25)Ni_(0.25)Co_(0.5)Sb_3

Nanostructured skutterudite-related compound Fe0.25Ni0.25Co0.5Sb3 was synthesized by a solvothermal method using FeCl3, NiCl2, CoCl2, and SbCl3 as the precursors and NaBH4 as the reductant. The solvothermally synthesized powders consisted of fine granules with an average particle size of tens of nanometers. The bulk material was prepared by hot pressing the powders. Transport property measurements indicated a heavily doped semiconductor behavior with n-type conduction. The thermal conductivity is about 1.83 W·m-1·K-1 at room temperature and decreases to 1.57 W·m-1·K-1 at 673 K. The low thermal conductivity is attributed to small grain size and high porosity. A maximum dimensionless figure of merit of 0.15 is obtained at 673 K.

Synthesis and fluorescence properties of cerium-KMgF_3 through a solvothermal process

Phosphor of KMgF3：Ce^3＋ is synthesized through solvothermal method at 180 ℃ and characterized by means of X-ray powder diffraction （XRD） and environment scanning electron microscopy （ESEM）. X-ray photoelectron spectroscopy （XPS） is applied to the study of the energy band structure of KMgF3：Ce^3＋ and confirms the oxygen content of the product is very low. The fluorescence spectra of the rare-earth ion-doped KMgF3 is investigated by the fluorescence spectrophotometer. In the emission spectra, there is a broadband emission with a maximum center located at 306 nm arising from d-f transition of Ce^3＋ in the host. This will be useful for ultraviolet tunable lasers.

Solvothermal Syntheses of (H_2en)_2Sn_2S_6·en and[(H_2hmda)_3(Hhmda)_2](Sn_2S_6)_2Using SnCl_4 and S_8 as Starting Materials

Three thiostannates （H2en）2Sn2S6· en 1, （Hen）4Sn2S6 2 （en = ethylenediamine, a known compound）and [（H2hmda）3（Hhmda）2]（Sn2S6）2 3 （hmda = hexamethylenediamine） were prepared using SnCl4.5H2O and S8 as starting materials in alkylenediamine solutions under mild solvothermal conditions. Compound 1 crystallizes in the triclinic system, space group P1^- with a = 8.7491（17）, b = 10.704（2）, c = 12.2031（19） A, a = 74.888（13）, β= 72.998（12）, γ= 89.032（15）°, V = 1052.9（3） A^3, Mr = 614.08, Z= 2, De = 1.937 g/cm^3, p = 2.966 mm^-1, F（000） = 604, S = 1.211, R = 0.0579 and wR = 0.0770 for 3999 observed reβections with I 〉 2σ（I）; while 3 crystallizes in the triclinic system, space group P1^- with a = 9.8075（13）, b = 10.8266（16）, c = 14.303（2） A, a = 88.611 （10）, β = 81.030（9）, γ = 74.609（9）°, V = 1446.1 （4） A^3, Mr = 1448.78, Z = 1, Dc = 1.664 g/cm^3, μ = 2.173 mm^-1, F（000） = 730, S = 1.173, R = 0.0457 and wR = 0.0667 for 5738 observed reβections with I 〉 2σ（I）. The compounds are composed of dimeric [Sn2S6]^4- anions and protohated alkylenediamine cations.

Solvothermal Synthesis and Structure Characterization of a 3D Hydrogen-bonded Copper Compound [Cu(H_2dhpmc)_2]·2H_2O

The solvothermal reaction of H3dhpmc (H3dhpmc = 2, 4-dihydroxypyrimidine- 5-carboxylic acid), CuCl2稨2O and NaVO3 results in the formation of a discrete mononuclear Cu(Ⅱ) complex [Cu(H2dhpmc)2]?H2O. It crystallizes in monoclinic system, space group P21/c with a = 5.0497(9), b = 10.0196(6), c = 13.715(2) ? b = 96.237(1)? V = 689.8(2) 3, Z = 2, Dc = 1.973 g/cm3, ?= 1.654 mm-1, F(000) = 414, R = 0.0736 and wR = 0.1351. Each Cu(Ⅱ) is coordinated to four oxygen atoms of two 2, 4-dihydroxypyrimidine-5-carboxylic acid ligands in the equatorial position and two oxygen atoms of two water molecules in the axial position to form an axially elongated octahedral geometry. The title complex is further linked into a three-dimensional structure through the weak interactions of hydrogen bonds between the oxygen atoms and the nitrogen atoms.

Solvothermal Synthesis, Crystal Structure and Luminescent Property of a Dy(Ⅲ) Coordination Polymer Constructed by 1,2,4,5-Benzenetetracarboxylic Acid

A three-dimensional coordination polymer {[Dy（H2btec）2/4（btec）3/6（H2O）]·2H2O} n has been synthesized through the reaction of DyCl3·6H2O and 1,2,4,5-benzenetetracarboxylic acid by solvothermal technique, and the crystal structure was determined by X-ray diffraction. The Dy（Ⅲ） coordination polymer crystallizes in monoclinic, space group P21/n with a=10.7063（1）, b=7.1491（1）, c=17.1197（3）, α=90, β=97.10, γ=90°, V=1300.31（3）3 , C10H9DyO11 , Dc=2.389g/cm3 , Z=4, F（000）=892, the final R=0.0165 and wR=0.0448 for I 〉 2σ（I）. The title coordination polymer possesses a three-dimensional framework consisting of nine-coordinate Dy（Ⅲ） centers and two kinds of coordination modes for the 1,2,4,5-benzenetetracarboxylic acid ligands. Every btec4- ligand （deprotonated four protons from 1,2,4,5-benzenetetracarboxylic acid） in the title coordination polymer can clamp three Dy atoms like forceps, which could make the Dy atoms closer in the area of metal-metal interaction. The 3-D framework of the coordination polymer has many channels occupied by the free guest water molecules, and the hydrogen bonds between the coordinated carboxylic groups and guest water molecules could stabilize the crystal structure of the title coordination polymer. In addition, the luminescence properties were also studied.

Solvothermal Synthesis and Characterization of [TM(1,2-dap)3]HgSb2Se5(TM = Co,Fe)with a Chain Structure

One organic-decorated quanternaery [TM（1,2-dap）3]Hg Sb2Se5（1,2-dap = 1,2-dianinopropane, TM = Co（1）, Fe（2）） compound has been solvothermally synthesized. The compounds crystallize in triclinic space group P 1, with a = 11.248（6）, b = 11.542（7）, c = 12.180（12） A, V =1268.7（16） A^3, Z = 2, F（000） = 1010 for 1 and a = 11.311（5）, b = 11.558（5）, c = 12.180（9） A, V =1276.5（12） A^3, Z = 2, F（000） = 1008 for 2. The crystal structure consists of one-dimensional anionics chains composed of Hg Se4 tetrahedra and SbSe3 trigonal pyramids sharing corners and[TM（dap）3]^2＋ cations. The [HgSb2Se＋5^2-]∞ anionic chains run along the [001] direction, and are surrounded by the [TM（dap）3]^2＋ cations. Meanwhile, 8-ring [Hg2Sb2Se4] and 6-ring [HgSb2Se2] are alternately found. The compounds were structurally characterized by elemental analysis,thermogravimetric analysis, infrared spectroscopy and UV-Vis diffuse reflectance spectroscopy.

Solvothermal Synthesis,Crystal Structure and Photoluminescence Property of a 3D Lead(Ⅱ)Coordination Polymer Based on Terephthalic Acid

Solvothermal reaction of Pb（NO3）2·6H2O with rigid linear ligand terephthalic acid（H2pta） in N,N-dimethylformamide（DMF） produced a new three-dimensional（3D） lead（Ⅱ）coordination polymer[Pb2（pta）1.5（μ4-OH）（DMF）]n 1,and its structure was characterized by single-crystal X-ray diffraction analyses.In polymer 1,the μ4-OH bridges the nearby lead（Ⅱ） ions into an infinite one-dimensional（1D） chain,and then the organic ligand pta^2- joins the neighbored chains into a 3D structure by two similar connection modes in different configurations.The solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta^2- and the p orbitals of the Pb^2＋ centers.