Synthesis of hybrid amorphous/crystalline SnO2 1D nanostructures: investigation of morphology, structure and optical properties

The aim of the study was to prepare SnO2 nanowires via a combination of electrospinning and the sol–gel method from a polyvinylpyrrolidone (PVP)/dimetylformamide (DMF)/ethanol(EtOH)/tin(IV) chloride pentahydrate (SnCl4·5H2O) solution. The morphology, structure and chemical composition of the obtained PVP/SnO2 nanofibers and SnO2 nanowires were examined using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) as well as a scanning electron microscope (SEM) with an energy dispersive spectrometer (EDX). The optical property analysis was performed on the basis of UV–Vis spectra of absorbance as a function of the wavelength, based on which the rated values of band gaps of the fabricated 1D nanostructures were determined. The morphology analysis showed that the obtained amorphous SnO2 nanowires with crystalline protuberances were characterized by a diameter of 50 to 120 nm. Results demonstrated that nanowires with a ratio of 1:1 precursor to polymer in the spinning solution were characterized by the smallest diameter after calcination and the smallest energy gap of 3.3 eV among all investigated samples. The rest of the studied materials were characterized by a larger energy gap (3.8 and 3.9 eV).

Crystal structures of four new iridium complexes, each containing a highly flexible carbodiphosphorane PCP pincer ligand

Compound [Ir(C8H12)(C51H45P4)]Cl2or [Ir(cod)(CH(dppm)2-κ3P,C,P)]Cl2(1a), was obtained from [IrCl(cod)]2and the carbodiphosphorane (CDP) salt [CH(dppm)2]Cl [where cod = cycloocta-1,5-diene and dppm = bis(diphenylphosphino)methane]. Treatment of1awith thallium(I) trifluoromethanesulfonate [Tl(OTf)] and subsequent crystallization gave complex [Ir(C8H12)(C51H45P4)](OTf)2·CH3CO2C2H5·CH2Cl2or [Ir(cod)(CH(dppm)2-κ3P,C,P)](OTf)2·CH3CO2C2H5·CH2Cl2(1b) [systematic name: (cycloocta-1,5-diene)(1,1,3,3,5,5,7,7-octaphenyl-1,7-diphospha-3,5-diphosphoniaheptan-4-yl)iridium(I) bis(trifluoromethanesulfonate)–ethyl acetate–dichloromethane (1/1/1)]. This five-coordinate iridium(I) complex cation adopts a trigonal–bipyramidal geometry with the CDP carbon and one cod double bond in axial sites. Compound1brepresents the first example of a non-meridionalcoordination of the PCP pincer ligand [CH(dppm)2]+with a P—Ir—P angle of 98.08 (2)°. Compound2, [IrCl2H(C51H44P4)]·(CH3)2CO or [IrCl2H(C(dppm)2-κ3P,C,P)]·(CH3)2CO [systematic name: dichloridohydrido(1,1,3,3,5,5,7,7-octaphenyl-1,5λ5,7-triphospha-3-phosphoniahept-4-en-4-yl)iridium(III) acetone monosolvate], crystallizes as an acetone monosolvate. It is a six-coordinate IrIIIcoordination compound. Here, the PCP pincer ligand is coordinated in ameridionalmanner; one chlorido ligand is positionedtransto the carbon donor, the remaining two coordination sites being occupied by the second chlorido and a hydrido ligandtransto each other. Complex3, [IrCl2H(C51H45P4)]Cl·5H2O or [IrCl2H(CH(dppm)2-κ3P,C,P)]Cl·5H2O [systematic name: dichloridohydrido(1,1,3,3,5,5,7,7-octaphenyl-1,7-diphospha-3,5-diphosphoniaheptan-4-yl)iridium(III) chloride pentahydrate], represents the conjugate CH acid of2. The ligand [CH(dppm)2]+is coordinated in ameridionalmanner. In the cationic six-coordinate IrIIIcomplex4, [IrClH(CO)(C51H44P4)]Cl·2CH3OH·H2O or [IrClH(CO)(C(dppm)2-κ3P,C,P)]Cl·2CH3OH·H2O [systematic name: carbonylchloridohydrido(1,1,3,3,5,5,7,7-octaphenyl-1,5λ5,7-triphospha-3-phosphoniahept-4-en-4-yl)iridium(III) chloride–methanol–water (1/2/1)], the chlorido ligand is found in the plane defined by the Ir center and themeridionalPCP ligand; the H and CO ligands are positioned axially to this plane andtransto each other.

Preparation of C60 Nanowhiskers-SnO2 Nanocomposites and Photocatalytic Degradation of Organic Dyes

C60 nanowhiskers were prepared using a liquid–liquid interfacial precipitation (LLIP) method. Tin oxide (SnO2) nanoparticles were synthesized by a reaction of tin (IV) chloride pentahydrate with ammonium nitrate in an electric furnace. The C60 nanowhiskers-SnO2 nanocomposites were calcined in an electric furnace at 700 °C under an inert argon gas atmosphere for 2 h. The crystallinity, morphology and optical properties of the samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and UV-vis spectrophotometry. The photocatalytic activity of the C60 nanowhiskers-SnO2 nanocomposites in the degradation of the organic dyes, such as methylene blue, methyl orange, rhodamine B, and brilliant green, under ultraviolet light at 254 nm by UV-vis spectrophotometry was evaluated and compared with that of C60 nanowhiskers and SnO2 nanoparticles. The experimental results showed that C60 nanowhiskers-SnO2 nanocomposites exhibited remarkably higher photocatalytic degradation of organic dyes compared to C60 nanowhiskers and SnO2 nanoparticles.

Surface Morphology and Electrical Properties of FTO (Fluorine Doped Tin Oxide) with Different Precursor Solution for Transparent Conducting Oxide

Fluorine doped tin oxide (FTO) thin film was prepared by using two different precursor solutions which are tin (ii) chloride dihydrate and tin (iv) chloride pentahydrate. These two precursors are used in spray pyrolysis process to prepare the fluorine doped tin oxide thin film. Surface Morphology of the thin film was characterized using field emission scanning electron microscope (FE-SEM). FESEM image shows the particle distribution and the morphology of fluorine doped tin oxide thin film. Two point probe I-V measurement and UV-Vis spectroscopy were used to study the electrical and optical properties of both films. Both precursors produced different particles distribution, electrical properties and also optical properties. The results show that the sheet resistance (Rs) of fluorine doped SnO2 is about 49.24×106Ω for tin (iv) chloride pentahydrate compared to 43.03×1012Ω for tin (ii) chloride dihydrate

Hydrothermal synthesis and crystal structure of a new lanthanum(III) coordination polymer with fumaric acid

The title compound, poly[diaquatris(μ4-but-2-enedioato)(μ2-but-2-enedioic acid)dilanthanum(III)], [La2(C4H2O4)3(C4H4O4)(H2O)2]n, was synthesized by the reaction of lanthanum chloride pentahydrate with fumaric acid under hydrothermal conditions. The asymmetric unit comprises an LaIIIcation, one and a half fumarate dianions (L2−), one a half-molecule of fumaric acid (H2L) and one coordinated water molecule. Each LaIIIcation has the same nine-coordinate environment and is surrounded by eight O atoms from seven distinct fumarate moieties, including one protonated fumarate unit and one water molecule in a distorted tricapped trigonal–prismatic environment. The LaO8(H2O) polyhedra centres are edge-shared through three carboxylate bridges of the fumarate ligand, forming chains in three dimensions to construct the MOF. The crystal structure is stabilized by O—H...O hydrogen-bond interactions between the coordinated water molecule and the carboxylate O atoms, and also between oxygen atoms of fumaric acid

Hydrothermal Synthesis and Photocatalytic Properties of TiO2/SnS2 Nanocomposite

TiO2/SnS2 nanocomposite was synthesized via hydrothermal treatment of tin (IV) chloride pentahydrate, thioacetamide and TiO2 nanotubes in deionized water at 150 °C for 3 h. The structure, composition and optical property of the as-synthesized nanocomposite were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra, and its photocatalytic property was tested in the reduction of aqueous Cr6+ under visible-light (λ > 420 nm) irradiation. It was observed that TiO2 nanotubes exhibited no photocatalytic activity, whereas TiO2/SnS2 nanocomposite exhibited photocatalytic activity in the reduction of aqueous Cr6+ under visible-light (λ > 420 nm) irradiation.

SnO2 Nanoparticle Synthesized by Ultrasonic-Assisted Process

SnO2 nanoparticles were synthesized by ultrasonic-assisted precipitation process using stannic chloride pentahydrate (SnCl4·5H2O) as a precursor. The stannic chloride aqueous solution was precipitated by ammonia under sonication. The as-synthesized precipitates were dried at 80 oC and then calcined at 400 oC for 2 h. The physical properties of nanoparticles with/without sonication were characterized by thermogravimetic and differential thermal analysis, X-ray diffraction, and transmission electron microscope. The results reveal that ultrasonic radiation has significant influence on phase transformation mechanism from Sn (OH)4 to SnO2, grain size and uniformity of SnO2 nanoparticles.