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Low concentrating photovoltaic (LCPV) system has been studied extensively, which showed excellent potential for the building integration application. However, such a system suffers from higher operating temperatures due to the concentrated light exposed into the solar cell. In this work, two different methods have been used to regulate the operating temperature of the solar cell without the interference of any other external mechanism. Two concepts were used to study the operating temperature of the solar cells are: i) use of Argon gas within the concentrator element, ii) incorporation of polymer-dispersed liquid crystal films (PDLC) on top of the module. In both cases, the power was improved by 37 mW–47 mW when temperature was reduced by 10 °C and 4 °C for the Argon gas-filled module and PDLC integrated module, respectively. In addition, the temperature effect of the PDLC integrated module showed a unique nature of reduction of the short circuit current due to the orientation of the liquid crystal particle, which increased at a higher temperature. The current study, therefore, shows the greater potential of improving the operating efficiency and reduction of solar cell temperature, without the need for additional pumping power such as needed for photovoltaic thermal application.

Herein, we report the synthesis of Cr incorporated ZnO sheets arrays microstructures and construction of photoelectrode through a direct aerosol assisted chemical vapour deposition (AACVD) method. The as-prepared Cr incorporated ZnO microstructures were characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, powdered X-ray spectroscopy, X-ray photoelectron spectroscopy and UV-Vis diffused reflectance spectroscopy. The Cr incorporation in ZnO red shifted the optical band gap of as-prepared photoanodes. The 15% Cr incorporation in ZnO has shown enhanced PEC performance. The AACVD method provides an efficient in situ incorporation approach for the manipulation of morphological aspects, phase purity, and band structure of photoelectrodes for an enhanced PEC performance.

A polymer gel electrolyte (PGE), using poly(styrene-co-acrylonitrile) (SAN) as a gelator, 1-butyl-3-methylimidazolium iodide (BMIMI) as the ionic liquid, and lithium iodide (LiI) as a source of iodide ions, is synthesized and investigated for its performance while employing it in a quasi-solid-state dye-sensitized solar cell using a N719 sensitizer and an I−/I3− redox couple. The PGEs are synthesized using different wt% of SAN and the relative amounts of LiI and I2 are optimized for iodide ion (I−) and triiodide ion (I3−) generation and their influence on the photovoltaic performance of the devices was investigated. On optimizing the PGE composition, the device gives an ionic conductivity of 7.00 mS cm−1, with a triiodide diffusion coefficient of 7.28 × 10−5 cm2 s−1, ensuring efficient polymer networks for the mobility of ionic species. The absorption edge for all PGEs lies close to ∼420 nm having transparency of more than 80% in the visible and NIR region. Impedance analysis evidently supports 17 wt% SAN as the optimum composition for PGE with better charge transfer and a decrease in recombination rate and considerable improvement in the electron lifetime. The highest photovoltaic conversion efficiency is 6.72% with the 17 wt% SAN PGE.

Electrochemical CO2 reduction reaction (CO2RR) provides a promising approach to curbing harmful emissions contributing to global warming. However, several challenges hinder the commercialization of this technology, including high overpotentials, electrode instability, and low Faradic efficiencies of desirable products. Several materials have been developed to overcome these challenges. This mini-review discusses the recent performance of various cobalt (Co) electrocatalysts, including Co-single atom, Co-multi metals, Co-complexes, Co-based metal–organic frameworks (MOFs), Co-based covalent organic frameworks (COFs), Co-nitrides, and Co-oxides. These materials are reviewed with respect to their stability of facilitating CO2 conversion to valuable products, and a summary of the current literature is highlighted, along with future perspectives for the development of efficient CO2RR.

In this work, we present an effective and facile approach for deposition of zinc oxide, and nickel incorporated zinc oxide thin films to fabricate photoanode of photoelectrochemical cell. Incorporation of Ni2+ in the host ZnO matrix results in the dramatic shape evolution of the resulting films from simple bullet like structures to complex punch like microstructures with increased estimated electrochemically active surface area. In addition to the role of Ni2+ in structure determination, it significantly enhanced the photoelectrochemical performance by improving the charge transport properties and conductivity of the parent host matrix. This work demonstrates a move towards tailoring functional properties of the films via controlled incorporation of different ionic species. This simple incorporation scheme can further be applied to attain a variety of compositionally tunable unique structures for desired applications by judiciously adjusting precursor choices and manipulating relative concentrations of the incorporated precursors during growth.

The development of low-cost, durable and efficient photocatalyst for overall photoelectrochemical water splitting is in demand to overcome the renewable energy crises. Herein, we demonstrate the efficient photoelectrochemical water splitting by cobalt (Co) incorporated zinc oxide (Zn1-xCoxO) thin films deposited via aerosol assisted chemical vapour deposition (AACVD) technique. The as-deposited Co incorporated ZnO thin films were characterised by powdered X-ray diffraction (pXRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and ultra violet-visible spectroscopy (UV-Vis). These films with different concentration of cobalt were investigated for water splitting applications and the best results were achieved for the films with 15% Co incorporation.

Porous ZnO/C nanocomposites derived from 3 different Zinc based metal-organic frameworks (MOFs) including MOF-5, MOF-74 and ZIF-8, were prepared at high temperature under water-steam atmosphere and their performances in photocatalytic H2 evolution reaction (HER) and photodegradation of organic dye pollutants were evaluated. The formation mechanism from MOF precursors, the structural properties, morphologies, compositions and textural properties of the derived ZnO/C composites were fully investigated based on different characterization techniques and the correlation between the precursors and the derived composites was discussed. It is evident that MOF precursors determine the crystalline structures, doping profiles, thermal stabilities and metal oxide-carbon weight percentage ratios of the resulting composites. The correlation between MOFs and their derived nanocomposites indicates that different parameters play unalike roles in photocatalytic performances. The desired properties can be tuned by selecting appropriate MOF precursors. MOF-5 derived porous ZnO/C nanocomposite not only exhibits the highest photocatalytic dye degradation activity under visible light among these MOFs, but also outperforms those derived from MOF-74 and ZIF-8 up to 9 and 4 times in photocatalytic HER respectively. This study offers simple and environmentally friendly approaches to further develop new homogeneously dispersed functional metal oxide/carbon composites for various energy and environment-related applications.

Photocatalysis is a classical solution to energy conversion and environmental pollution control problems. In photocatalysis, the development and exploration of new visible light catalysts and their synthesis and modification strategies are crucial. It is also essential to understand the mechanism of these reactions in the various reaction media. Recently, bismuth and graphene’s unique geometrical and electronic properties have attracted considerable attention in photocatalysis. This review summarizes bismuth-graphene nanohybrids’ synthetic processes with various design considerations, fundamental mechanisms of action, heterogeneous photocatalysis, benefits, and challenges. Some key applications in energy conversion and environmental pollution control are discussed, such as CO2 reduction, water splitting, pollutant degradation, disinfection, and organic transformations. The detailed perspective of bismuth-graphene nanohybrids’ applications in various research fields presented herein should be of equal interest to academic and industrial scientists.

3D porous, thin sheet-like rGO aerogel was fabricated to explore its antimony (Sb) removal potential from wastewater. Langmuir isothermal and pseudo-second-order kinetic model best-suited the adsorption process. The maximum adsorption capacities were 168.59 and 206.72 mg/g for Sb (III and V) at pH 6.0 respectively. The thermodynamic parameters designated the process to be thermodynamically spontaneous, endothermic reaction, a result of dissociative chemisorption. The rGO aerogel bestowed good selectively among competing ions and reusability with 95% efficiency. rGO posed excellent practicability with Sb-spiked tap water and fixed-bed column experiments showing 97.6% of Sb (III) (3.6 μg/L) and 96.8% of Sb (V) (4.7 μg/L) removal from tap water and from fixed column bed experiments breakthrough volumes (BV) for the Sb (III) and Sb (V) ions were noted to be 540 BV and 925 BV respectively, until 5 ppb, which are below the requirement of MCL for Sb in drinking water (6 μg/L). XPS and DFT analyses explained adsorption mechanism and depicted a higher affinity of Sb (V) towards rGO surface than Sb (III).

The design and synthesis of a highly active noble metal-free electrocatalyst for hydrogen evolution reaction (HER) from water splitting are crucial for renewable energy technologies. Herein, we report the growth of molybdenum disulfide (MoS2) on N-doped carbon encapsulated metal particles (M@NDC@MoS2, where M = Co, Fe or CoFe alloy) as a highly active electrocatalyst for HER. The hierarchical MoS2 nanosheets are grown on M@NDC using the hydrothermal method. Our results show that CoFe@NDC@MoS2 hybrid spheres exhibit excellent HER performance with an overpotential of 64 mV at a current density of 10 mA cm−2 and a small Tafel slope of 45 mV dec-1. In addition, CoFe@NDC@MoS2 hybrid spheres have good long-term stability and durability in acidic conditions. Besides, density functional theory (DFT) simulations of the proposed catalysts are performed and suggest that the superior catalytic activity of CoFe@NDC@MoS2 is due to the optimal electron transfer from CoFe@NDC nanoparticles to MoS2 nanosheets. This electron transfer facilitates H+ interaction and adsorption, leading to a decreased Gibbs free energy (ΔGH* ≈ 0.08 eV) and local work function on the surface, which consequently enhances the HER performance.

Monoclinic clinobisvanite BiVO4 is one of the most promising materials in the field of solar water splitting due to its band gap and suitable valence band maximum (VBM) position. We have carried out comprehensive experimental and periodic density functional theory (DFT) simulations of BiVO4 heterojunction with selenium (Se-BiVO4), to understand the nature of the heterojunction. We have also investigated the contribution of Se to higher performance by effecting morphology, light absorption, and charge transfer properties in heterojunction. Electronic properties simulations of BiVO4 show that its VBM and conduction band minimum (CBM) are comprised of O 2p and V 3d orbitals, respectively. The Se/BiVO4 heterojunction has boosted the photocurrent density by 3-fold from 0.7 to 2.2 mA cm–2 at 1.3 V vs SCE. The electrochemical impedance and Mott–Schottky analysis result in favorable charge transfer characteristics, which account for the higher performance in Se/BiVO4 as compared to the BiVO4 and Se. Finally, spec...

Density functional theory (DFT) study of polypyrrole-TiO 2 composites has been carried out to explore their optical, electronic and charge transfer properties for the development of an efficient photocatalyst. Titanium dioxide (Ti 16 O 32 ) was interacted with a range of pyrrole (Py) oligomers to predict the optimum composition of nPy-TiO 2 composite with suitable band structure for efficient photocatalytic properties. The study has revealed that Py-Ti 16 O 32 composites have narrow band gap and better visible light absorption capability compared to individual constituents. The simulated results of band structure (band gap, and band edge positions), molecular orbitals, and UV–vis spectra of the optimized nPy-Ti 16 O 32 systems strongly support the existence of strong interactions between Py and TiO 2 in the composite. A red-shifting in λ max , narrowing band gap, and strong intermolecular interaction energy (-41 to −72 kcal/mol) of nPy-Ti 16 O 32 composites confirm the existence of strong covalent type interactions. Electron−hole transferring phenomena are simulated with natural bonding orbital analysis where Py oligomers found as donor and Ti 16 O 32 as an acceptor in nPy-Ti 16 O 32 composites.

Density functional theory study has been carried out to design a new All-Solid-State dye-sensitized solar cell (SDSC), by applying a donor-acceptor conjugated polymer instead of liquid electrolyte. The typical redox mediator (I 1− /I 3− ) is replaced with a narrow band gap, hole transporting material (HTM). The electronic and optical properties predict that donor and acceptor moieties in the polymeric body have increased the visible light absorption and charge transporting ability, compared to their parent polymers. A unique “upstairs” like band energy diagram is created by packing N3 between HTM and TiO 2 . Upon light irradiation on the proposed configuration, electrons will move from the dye to TiO 2 and from HTM to dye (to regenerate dye), simultaneously. Our theoretical simulations prove that the proposed configuration will be highly efficient as the HOMO level of HTM is 1.19 eV above the HOMO of sanitizer (dye); providing an efficient pathway for charge transfer. High short-circuit current density and power conversion efficiency is promised from the strong overlapping of molecular orbitals of HTM and sensitizer. A low reorganization energy of 0.21 eV and exciton binding energy of 0.55 eV, confirm the high efficiency of HTM. Finally, a theoretical open-circuit voltage of 1.49 eV would results high quantum yield while, the chemical stability of HTM towards oxidation can be estimated from its high ionization potential value (4.57 eV).

Nanostructured Bi2WO6 thin film electrodes with enhanced solar energy conversion and photocatalytic properties have been fabricated using Aerosol-Assisted Chemical Vapor Deposition (AACVD). By conveniently controlling the deposition process parameters, Bi2WO6 electrodes were fabricated with nanoplates and hierarchical buckyball-shaped microsphere structures morphology. A detailed study has been conducted to correlate the structure and morphology with the photoelectrochemical (PEC) and photocatalytic dye degradation performance. The PEC investigations revealed that the hierarchical buckyball-shaped microsphere structured Bi2WO6 electrodes have shown the photocurrent density of 220 &mu, Acm&minus, 2 while nanoplates have a photocurrent density of 170 &mu, 2 at 0.23 V (vs. Ag/AgCl/3M KCl) under AM1.5 illumination. The PEC characterization of Bi2WO6 electrodes also reveals that the photocurrent density and photocurrent onset potential is strongly dependent on the orientation and morphology, hence the deposition parameters. Similarly, the methylene blue (MB) and rhodamine B (RhB) photodegradation performance of Bi2WO6 electrodes also show a strong correlation with morphology. This finding provides an appropriate route to engineer the energetic and interfacial properties of Bi2WO6 electrode to enhance solar energy conversion and the photocatalytic performance of semiconductor materials.

Heterogeneous photocatalysis, employing semiconductor metal oxides, especially at nano scale is a promising technique to mortify the dye residues from effluent. The photocatalysts on doping with a suitable dopant can be modified to enhance the photocatalytic activity. In this study, undoped and series of Fe3+ doped ZnO have been grown on polyester fabric through low temperature hydrothermal method to generate photocatalytic membrane reactors (PMRs). The material grown on the surface of fabric was characterized by XRD, EDX, SEM, TEM, STEM, AFM, XPS, ICP-MS, DRS and PL studies. For ZnO/PMR and Fe3+@ZnO/PMR photocatalytic activity was determined and examined to increase for Fe3+@ZnO/PMR in the solar region due to the reduction of band gap from 3.2 to 2.6 eV on Fe3+doping. The surface properties of PMRs were also determined by zeta potential and contact angle. The characterized ZnO and Fe3+@ZnO nano discs based PMRs have been used to degrade RB5 reactive dye on irradiating with artificial sunlight (D65, 72 W). The reaction parameters i.e. initial dye and oxidant concentration, pH and irradiation time have been optimized by Response Surface Methodology (RSM). The extent of dye degradation has been evaluated by UV/vis spectroscopy and FTIR. The maximum degradation achieved was 88.89% for ZnO/PMR and 98.34% for Fe3+@ZnO PMR in 180 min. The photocatalytic efficiency of Fe3+@ZnO PMR was investigated for 15 batches, with a slight gradual decrease in activity after eight batches.

Transition metal ion incorporation has been emerged as an effective stratagem to enhance the performance of metal oxide photoanodes. In the present work, we design and fabricate the plain ZnO and (2, 5, 10 and 15%) Fe incorporated ZnO photoanodes by aerosol assisted chemical vapor deposition (AACVD) method. The 15% Fe incorporated ZnO photoanode displayed excellent photocurrent density of 4.6 mA/cm 2 at 0.7 VAg/AgCl with photo conversion efficiency of 2.4%, which is 159 times higher than pure ZnO photoanode (0.028 mA/cm2). The obtained results are remarkably superior to the previous results. Furthermore, the Fe incorporated photoelectrodes have also shown good stability. The excellent photoelectrochemical performance of Fe incorporated ZnO showed red shift in band edge with relative decrease in the band gap energy compared to pure ZnO. The demonstration of this simple method for the deposition of Fe incorporated ZnO to fabricate highly efficient photoanode for the PEC water splitting can easily be applied to other similar systems.

Quantum mechanical calculations are performed to establish the structure of an oligomer of aniline and pyrrole [Poly(Ani-co-Py)], through comparison of experimental and theoretically calculated properties, including conductivity. The copolymer was synthesized through chemical oxidative polymerization and then confirmed from the experimental IR, UV–vis, mass spectra, elemental, XRD, TGA, and SEM analysis. Quantum mechanical calculations are performed at Density Functional Theory (DFT) and Time dependent DFT (TD-DFT) methods for the electronic and spectroscopic properties of the oligomer. A very nice correlation is found between the theory and experiment which consequences the structure of Poly(Ani-co-Py). Poly(Ani-co-Py) is not explored like other conducting polymers; however, by tuning this molecular structure, the electro-active nature of this material can be enhanced adequately.

Sensitivity and selectivity of polypyrrole (PPy) toward NH3, CO2, and CO have been studied at density functional theory (DFT). PPy oligomers are used both in the doped (PPy+) and neutral (PPy) form...

Bimetallic chlorodi-/triorganotin(IV) derivatives of general formulas R2(H2O)SnLCSSSn(Cl)R2 (R=Me: 1; Ph: 2) and R3Sn(Na)LCSSSnR3·H2O (R=Bu: 3; Ph: 4) were prepared by reaction of iminodiacetic acid disodium salt hydrate (Na2LH) with CS2 and R2SnCl2/R3SnCl in methanol. The reaction between Na2LH, CS2, and PdCl2 produced [Na2LCSS]2Pd·2H2O (5) which was treated with R3SnCl to synthesize the heterobimetallic derivatives [R3Sn(Na)LCSS]2Pd·2H2O (R=Me: 6; Ph: 7). The complexes were characterized by microanalysis, spectroscopic, and thermogravimetric analyses. Elemental analysis data, mass fragmentation, and thermal degradation patterns supported the molecular composition of the complexes. FT-IR data indicated monodentate binding of carboxylate while a chelating coordination mode of the dithiocarboxylate was verified in the solid state. A five-coordinate tin(IV) was demonstrated in the solid state. In solution, a tetrahedral/trigonal bipyramidal configuration around Sn(IV) and a square planar geometry of Pd(II) was indicated by multinuclear NMR (1H and 13C) and UV-visible studies. The Pd(II) derivatives showed interaction with salmon sperm-DNA and caused an inhibition of alkaline phosphatase (ALPs). The antibacterial/antifungal potential of the coordination products varied with the nature of incorporated metal and a substitution pattern at tin(IV); the palladium metallation decreased the antimicrobial activities. The triorganotin(IV) products exhibited more powerful action against bacteria/fungi as compared to their diorganotin(IV) counterparts. The complexes displayed sufficiently lower hemolytic effects in vitro as compared to triton X-100 and slightly higher than PBS.

Platinum-free counter electrodes are crucial for developing cost effective solar energy harvesting technology. We describe here the fabrication of efficient platinum free FTO counter electrodes for dye sensitized solar cells based on pristine polyaniline, polyaniline doped with sulfuric acid, ammonuim lauryl sulfate, as well as binary doped with sulfuric acid and ammonium lauryl sulphate. The characteristics of these counter electrodes were analyzed using cyclic voltammetry, photocurrent density–voltage and electrochemical impedance spectroscopy measurements. At optimized fabrication conditions, the counter electrode shows significantly high photoelectric conversion efficiency of 4.54% compared to 4.03% for reference platinum counter electrode. Charge transfer resistance at the interface between electrolyte and counter-electrode is also decreased for the optimized polyaniline based counter electrode. Furthermore, the device presented characteristics of multiple start/stop ability and fast activity. The simple preparation procedure, low cost and improved photoelectric properties permit fabricated counter electrode to be a reliable alternative for dye sensitized solar cells.

Acanthite (Ag2S) thin films were fabricated on fluorine doped tin oxide coated conducting glass substrates by aerosol assisted chemical vapor deposition (AACVD) using silver cluster [Ag4{S2CN(C2H5)2}3(C5H5N)2]n·nNO3·2nH2O (1) [where (S2CN(C2H5)2) = diethyldithiocarbamate, C5H5N = pyridine] as a single source precursor. Cluster (1) was synthesized by the reaction of sodium diethyldithiocarbamate with silver nitrate in a mixture of acetone and pyridine. (1) was analyzed by melting point, elemental analysis, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, thermogravimetry and single crystal X-ray studies. Single crystal X-ray studies showed that (1) crystallizes in the triclinic crystal system with a = 11.4372(3), b = 11.6768(3), and c = 16.3672(4) A and α = 105.817(3), β = 97.891(3), and γ = 93.274(3)° in the space group P-1. Thermogravimetric analysis revealed that (1) undergoes facile thermal decomposition at 400 °C to give a stable residual mass consistent with the formation of Ag2S. Thin films grown from a 0.02 M solution of (1) in pyridine at 350 and 400 °C using AACVD technique were characterized by powder X-ray diffraction, field emission scanning electron microscopy (FESEM), energy dispersive X-ray and ultraviolet-visible spectrophotometry. FESEM images of the films exhibited well-defined nanorods with length > 1000 nm and diameter 100–150 nm grown without any cracks, fractures or directional preference. A band gap of 1.05 eV was estimated by extrapolating the linear part of a Tauc plot recorded for the films. The photoelectrochemical (PEC) characteristics recorded under Air Mass 1.5 illumination indicated a photocurrent density of 220 μA cm− 2 at 0.0 V vs Ag/AgCl/3 M KCl. The optical and PEC characteristics of the deposited thin films proved their suitability for PEC applications.

New hexanuclear zinc complex, Zn6(OAc)8(μ-O)2(dmae)4 (1) (OAc = acetato, dmae = N,N-dimethyl aminoethanolato) has been synthesized and characterized by its melting point, elemental analysis, Fourier transform infrared spectroscopy, atmospheric-pressure chemical-ionization mass spectrometry, thermal gravimetric analysis, and single crystal X-ray analysis. The complex (1) crystallizes in the monoclinic space group C2/c. The high solubility of complex (1) in organic solvents such as alcohol, THF, and toluene and low decomposition temperature as compared to Zn(OAc)2 make it a promising single source candidate for the deposition of nanostructured ZnO thin films by aerosol-assisted chemical vapor deposition. Films with various nanostructures, morphology, and crystallographic orientation have been deposited by controlling the deposition temperature. The deposited films have been characterized by X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray analysis. The optical characterization of...

Graphene (GR) and its derivatives are promising materials on the horizon of nanotechnology and material science and have attracted a tremendous amount of research interest in recent years. The unique atom-thick 2D structure with sp(2) hybridization and large specific surface area, high thermal conductivity, superior electron mobility, and chemical stability have made GR and its derivatives extremely attractive components for composite materials for solar energy conversion, energy storage, environmental purification, and biosensor applications. This review gives a brief introduction of GR's unique structure, band structure engineering, physical and chemical properties, and recent energy-related progress of GR-based materials in the fields of energy conversion (e.g., photocatalysis, photoelectrochemical water splitting, CO2 reduction, dye-sensitized and organic solar cells, and photosensitizers in photovoltaic devices) and energy storage (batteries, fuel cells, and supercapacitors). The vast coverage of advancements in environmental applications of GR-based materials for photocatalytic degradation of organic pollutants, gas sensing, and removal of heavy-metal ions is presented. Additionally, the use of graphene composites in the biosensing field is discussed. We conclude the review with remarks on the challenges, prospects, and further development of GR-based materials in the exciting fields of energy, environment, and bioscience.

A single molecular heterobimetallic complex, [Co2Ti(m3-O)(TFA)6(THF)3] (1) [TFA=trifluoroacetate, THF=tetrahydrofuran], was synthesized, structurally and spectroscopically characterized and implemented as a single-source precursor for the preparation of CoTiO3–CoO composite thin films by aerosol-assisted chemical vapour deposition (AACVD). The precursor complex was prepared by interaction of Co(OAc)2.4H2O [OAc=(CH3COO � )] with Ti(iso-propoxide)4 in the presence of trifluoroacetic acid in THF, and was analysed by melting point, CHN, FT-IR, single-crystal X-ray diffraction and thermogravimetric analysis. The precursor complex thermally decomposed at 480 � C to give a residual mass corresponding to a CoTiO3–CoO composite material. Good-quality crystalline CoTiO3–CoO composite thin films deposited at 500 � C by AACVD and characterized through powder X-ray diffraction and scanning electron microscopy/energy-dispersive X-ray spectroscopy shows that the crystallites have a rose-flower-like morphology with an average petal size in the range of 2–6mm. Copyright © 2012 John Wiley & Sons, Ltd.

Inhibition effects of novel organotin(IV) esters of (E)-4-oxo-4-((3-trifluoromethyl)phenyl)amino)but-2-enoic acid have been studied against bacterial, fungal, tumoral and insecticidal strains. The complexes have shown potency against all these strains and is attributed to the multiple interactive sites of the ligand that not only change the environment around tin but also can make interactions with DNA. The synthesized complexes were characterized by physical, spectral, analytical and multinuclear nmr (1H, 13C, 119Sn) data. The X-ray structure analysis of the complex is reported.

A heterobimetallic single molecular precursor, [Fe2Ti4(μ-O)6(TFA)8(THF)6] (1) [TFA = trifluoroacetate, THF = tetrahydrofuran], was synthesized by the simple reaction of [Fe3O(OAc)6(H2O)3]NO3·4H2O [OAc = acetato] with tetrakis(2-ethoxyethanalato)titanium(IV) in the presence of trifluoroacetic acid in THF. The synthesized precursor was analyzed by melting point, CHN analysis, FTIR, single crystal X-ray diffraction and thermogravimetric analysis. Complex (1) crystallizes in the orthorhombic space group Pca21 with cell dimensions a = 19.2114(14), b = 20.4804(15) and c = 17.2504(12) A, and the complex undergoes thermal decomposition at 490 °C to give a residual mass corresponding to an Fe2TiO5–TiO2 composite mixture. The synthesized precursor was utilized for deposition of Fe2TiO5–TiO2 composite thin films by aerosol-assisted chemical vapor deposition (AACVD) on glass substrates at 500 °C using argon as the carrier gas. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray powder diffraction (XRD) analyses of the thin films suggest the formation of good quality crystalline thin films of an Fe2TiO5–TiO2 composite with an average grain size of 0.105–0.120 μm.

The demand for nanostructured metal oxide electrodes in optoelectronic devices requires investigation of simple and scalable deposition processes. In this study we demonstrate the flexibility of aerosol-assisted chemical vapor deposition to fabricate single and mixed oxide electrodes. The composition, structure, and morphology can easily be controlled by varying the Zn:Sn ratio of the precursor solution. X-ray diffractometric analysis proved that the structure and composition were strongly dependent on the Zn concentration in the precursor. ZnO, SnO2, and a range of ZnO/SnO2 composite electrodes were fabricated by gradually decreasing the Zn content in the precursor solution. A diverse range of nanostructures were also created as the Zn:Sn ratio was varied. The morphology of the electrodes changed from nanoparticles, to nanoplates and nanocolumns with the change in the Zn:Sn ratio. Diffuse reflectance spectroscopy confirmed the high optical absorption of the materials in the UV region. It was found that by controlling the Zn:Sn ratio of the precursor, the optical properties of the electrodes could be finely tuned between the bandgap (Eg) of ZnO (Eg∼3.31 eV) and SnO2 (Eg∼3.55 eV).

Semiconducting nanocrystalline ZnFe 2 O 4 thin films were deposited by aerosol-assisted chemical vapour deposition (AACVD) for photoelectrochemical (PEC) water splitting. The effect of deposition parameters such as solvent type, temperature and deposition time on PEC properties has been investigated. The SEM analysis illustrated that the morphology of the films changes significantly with the change of solvent. The films deposited from ethanolic precursor solution have a morphology consisting of interconnected cactus-like ZnFe 2 O 4 structure growing vertically from the FTO substrate. The current–voltage characterization proved that the nanocrystalline ZnFe 2 O 4 electrodes exhibit n -type semiconducting behaviour and the photocurrent was found strongly dependent on the deposition solvent, deposition temperature and deposition time. The maximum photocurrent density of 350 μA/cm 2 at 0.23 V vs. Ag/AgCl/3 M KCl (∼1.23 V vs. RHE) was obtained for the ZnFe 2 O 4 electrode synthesized using the optimum deposition temperature of 450 °C, the deposition time of 35 min, and 0.1 M solution of ( 1 ) in ethanol. The electrode gave an incident photon to electron conversion efficiency of 13.5% at an applied potential of 0.23 V vs. Ag/AgCl/3 M KCl at 350 nm. The donor density of the ZnFe 2 O 4 was 3.24 × 10 24 m −3 and the flatband potential is approximately −0.17 V, which remarkably agrees with the photocurrent onset potential of −0.18 V vs. Ag/AgCl/3 M KCl.

Bi2S3 nanotubes and nanoparticle in the form of thin films were deposited on fluorine doped SnO2 (FTO) coated conducting glass substrates by Aerosol Assisted Chemical Vapor Deposition (AACVD) using tris-(N,N-diethyldithiocarbamato)bismuth(III), [Bi(S2CN(C2H5)2)3]2 (1) as a precursor. Thin films were deposited from solutions of (1) in either chloroform, dichloromethane, or a 1:1 mixture of chloroform and toluene at temperature between 350 to 450 °C and characterized by X-ray diffraction (XRD), UV−vis spectroscopy, field emission gun scanning electron microscopy (FEGSEM), and energy dispersive X-ray (EDX) analysis. FEGSEM images of films deposited from chloroform or dichloromethane exhibit well-defined and evenly distributed nanotubes with an average internal diameter of 40 nm. Films deposited from chloroform/toluene, on the other hand, have compact nanostuctured morphology. Bandgaps of 1.85 and 1.8 eV were estimated for nanotubes and nanoparticles, respectively, by extrapolating the linear part of the Tauc...

This article describes the synthesis of triorganotin(IV)-, chlorodiorganotin(IV)- and diorganotin(IV) 4-ethoxycarbonylpiperazine-1-carbodithioates with general R3SnL {where R = CH3 (1), n-C4H9 (2) and C6H5 (3)}, R2SnClL {where R = CH3 (4), n-C4H9 (5) and C6H5 (6)} and R2SnL2 {where R = CH3 (7), n-C4H9 (8) and C6H5 (9)}, respectively. The coordination behavior of ligand (L) in all compounds was investigated by different analytical techniques such as FT-IR and multinuclear NMR. X-ray single crystal analysis confirmed supramolecular structure for compounds (3) and (4) with distorted trigonal-bipyramidal and distorted square-pyramidal geometries, respectively. The compounds have pronounced antimicrobial (antibacterial and antifungal) potency and moderate insecticidal activity. These compounds also inhibit effectively the activity of urease enzyme.

α-Fe2O3 thin film photoelectrodes were fabricated by aerosol-assisted chemical vapor deposition (AACVD) using a new hexanuclear iron precursor [Fe6(PhCOO)10(acac)2(O)2(OH)2]·3C7H8 (1) (where PhCOO = benzoate and acac = 2,4-pentanedionate). The precursor (1) designed for AACVD has a low decomposition temperature and sufficient solubility in organic solvents and was synthesized by simple chemical techniques in high yield. It was characterized by melting point, FT-IR, X-ray crystallography, and thermogravimetry (TGA). The TGA analysis proved that complex (1) undergoes facile thermal decomposition at 475 °C to give iron oxide residue. In-house designed AACVD equipment was used to deposit highly crystalline thin films of α-Fe2O3 on fluorine-doped SnO2 coated glass substrates at 475 °C in a single step. The material properties were characterized by XRD, XPS, and Raman spectroscopy, and the results confirmed that films were highly crystalline α-Fe2O3 and free from other phases of iron oxide. Further analysis of ...

Homobi-, -tri- and -tetranuclear copper(II) oligomeric complexes, [Cu(dmap)(OAc)(H2O)]2·H2O (1), [Cu3(dmae)3(acac)2Cl] (2) and [Cu(dmae)(TFA)]4 (3), have been prepared by reacting Cu(OAc)2·H2O with dmapH, [Cu(dmae)Cl]4 with Na(acac) and Cu(dmae)2 with Cu(TFA)2 [dmae = (N,N-dimethylamino)ethanolate, dmap = (N,N-dimethylamino)propanolate, TFA = trifluoroacetate, and acac = 2,4-pentanedionate], respectively and characterized by melting point, elemental analysis, FT-IR and single-crystal X-ray diffraction. The crystal analysis shows that bi- (1) and trinuclear (2) complexes crystallize in the triclinic, while the tetranuclear complex 3 belongs to the monoclinic crystal system. TGA and AACVD experiments prove that the complexes undergo facile thermal decomposition in the temperature range 300–460 °C to deposit thin films of pure copper metal. The SEM and XRD analyses of the thin films suggest the formation of Cu crystallites with grain sizes of 100–340 nm (for 1), 75.4–90.8 nm (for 2 and 3). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Nanostructured thin films of α-Fe2O3 were prepared through atmospheric chemical vapour deposition (APCVD) using ferrocene and iron pentacarbonyl as precursors. Higher optical absorption was observed for hematite films prepared using ferrocene, which was attributed to the higher packing density. Photoelectrochemical (PEC) studies of the films prepared using ferrocene showed superior performance to that of iron pentacarbonyl. Photocurrent density of 540 µA/cm2 and 1.5 µA/cm2 at 1.23 VRHE was achieved for hematite films prepared using ferrocene and iron pentacarbonyl, respectively. Our findings suggest that ferrocene can be used as a promising alternative to iron pentacarbonyl to prepare hematite photoelectrodes using APCVD.

The high nuclearity zinc complex, Zn-6(OAc)(8)(mu-OH)(2)(dmae)(2)(dmaeH)(2) (1) (OAc = acetate and dmaeH = N,N'-dimethylaminoethanol), having a low decomposition temperature and sufficiently high solubility in non-polar solvents, was synthesized by a simple chemical technique in high yield and analyzed by melting point, elemental analysis, FTIR, NMR, single crystal X-ray crystallography and thermal analysis. Aerosol-assisted chemical vapor deposition technique was used to deposit a high-quality thin film with good adhesion to the glass substrate at relatively low temperature (320 degrees C). Scanning electron microscopy of the film shows clearly distinct crystallites of uniform shape with 2.4-2.9 mu m size. Powder X-ray diffraction measurements have indicated the deposition of a crystalline phase of hexagonal ZnO with space group P63mc. (c) 2007 Elsevier B.V. All rights reserved.

Heterobimetallic molecular precursors [Ti4(dmae)6(mu-OH)(mu-O)6Cu6(OAc)9.H2O] (1) and [Zn7(OAc)10(mu-OH)6Cu5(dmae)4Cl4] (2) for the deposition of metal oxide thin films of Cu6Ti4O12 (Cu3TiO4, TiO2) and Cu5Zn7O12 (ZnO, CuO) were prepared by the interaction of Ti(dmae)4 with Cu(OAc)2.2H2O for 1 and tetrameric (N,N-dimethylamino)ethanolatocopper(II) chloride, [(dmae)CuCl]4 [where dmae = (N,N-dimethylamino)ethanolate] with Zn(OAc)2.2H2O (where OAc = acetate) for 2 in dry toluene. Both complexes were characterized by melting point, elemental analysis, Fourier transform IR, fast atom bombardment mass spectrometry, thermal analysis (TGA), and single-crystal X-ray diffraction. TGA and XRD prove that complexes 1 and 2 undergo facile thermal decomposition at 300 and 460 degrees C to form thin films of Cu/Ti and Cu/Zn mixed-metal oxides, respectively. Scanning electron microscopy and XRD of the thin films suggest the formation of impurity-free crystallite mixtures of Cu3TiO4 and TiO2, with average crystallite sizes of 22.2 nm from complex 1 and of ZnO and CuO with average crystallite sizes of 26.1 nm from complex 2.

Density functional theory (DFT) and phytochemical study of a natural product, Diospyrin (DO) have been carried out. A suitable level of theory was developed, based on correlating the experimental and theoretical data. Hybrid DFT method at B3LYP/6-31G (d,p) level of theory is employed for obtaining the electronic, spectroscopic, inter-molecular interaction and thermodynamic properties of DO. The exact structure of DO is confirmed from the nice validation of the theory and experiment. Non-covalent interactions of DO with different atmospheric gases such as NH3, CO2, CO, and H2O were studied to find out its electroactive nature. The experimental and predicted geometrical parameters, IR and UV–vis spectra (B3LYP/6-31+G (d,p) level of theory) show excellent correlation. Inter-molecular non-bonding interaction of DO with atmospheric gases is investigated through geometrical parameters, electronic properties, charge analysis, and thermodynamic parameters. Electronic properties include, ionization potential (I.P.), electron affinities (E.A.), electrostatic potential (ESP), density of states (DOS), HOMO, LUMO, and band gap. All these characterizations have corroborated each other and confirmed the presence of non-covalent nature in DO with the mentioned gases.

Thin films of halide free Cu–Co mixed metal oxide have been prepared at 390 °C from the heterobimetallic complex Co4(THF)4(TFA)8(μ-OH)2Cu2(dmae)2 · 0.5C7H8 (1) [dmae = N,N-dimethylaminoethanol ((CH3)2NCH2CH2O−), TFA = triflouroacetate (CF3COO−), THF = tetrahydrofurane (C4H8O)] which was prepared by the reaction of [Cu(dmae)Cl]4 and Co(TFA)2 · 4H2O. The precursor was characterized for its melting point, elemental composition, FTIR and X-ray single crystal structure determination. Thin films grown on glass substrate by using AACVD out of complex 1 were characterized by XRD and SEM. TGA and AACVD experiments reveal it to be a suitable precursor for the deposition of halide free Cu–Co mixed-metal oxide thin films at relatively low temperatures.

The Cu atom in the title complex, [Cu(C9H7O2)(C4H11NO)2], lies on an inversion centre in an octa­hedral geometry and is coordinated by two bidentate chelating 2-(dimethyl­amino)ethanol groups and two monodentate cinnamate groups which are mutually trans to each other. The non-coordinated O atoms of the cinnamate ligands form intra­molecular hydrogen bonds to the OH groups of the 2-(dimethyl­amino)ethanol ligands, generating six-membered rings.

In the title compound, [Pd(C4H10NO)Cl(C4H11NO)], the geometry around the Pd atom, which is coordinated by one O, one Cl and two N atoms, is square-planar, with the N atoms trans to each other. One deprotonated N,N-dimethylaminoethanol (dmaeH) molecule acts as a bidentate ligand, while the other is coordinated through the N atom only. The structure displays O—H...O hydrogen bonding.

The structure of the title complex, [Ni2(C5H7O2)4(H2O)2]·0.5H2O, is dimeric and corresponds to the trimeric structure of bis­(acetyl­acetonato)nickel(II) in which one Ni(acac)2 unit is replaced by two water mol­ecules. The centrosymmetric mol­ecule comprises two O–O edge-shared octa­hedra. The asymmetric unit contains two half-molecules of the complex and one water molecule.