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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.

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).

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.

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...

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.

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).

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...

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)

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.

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.

The crystal structure of the title compound, [Pd(C5H7O2)2], has been redetermined at 100 K using modern equipment, resulting in improved precision compared to the previous study [Knyazeva et al. (1970). Zh. Strukt. Khim. 11, 938–939]. The new measurements reveal that the plane of the 2,4-penta­nedionate ligand is tilted by 3.4 (1)° with respect to the PdO4 unit (Pd site symmetry = \overline{1}). Possible reasons for this bending are examined in terms of previously undiscussed inter­molecular inter­actions.

Heterobimetallic molecular precursors [Ti(4)(dmae)(6)(mu-OH)(mu-O)(6)Cu(6)(benzoate)(9)] (1) and [Ti(4)(dmae)(6)(mu-OH)(mu-O)(6)Cu(6)(2-methylbenzoate)(9)] (2) were prepared by the interaction of Ti(dmae)(4) [dmae=N,N-dimethylaminoethanolate] with Cu(benzoate)(2).2H(2)O for (2) and Cu(2-methylbenzoate)(2).2H(2)O for (2), respectively, in dry toluene, for selective deposition of Cu/Ti oxide thin films for possible technological applications. Both the complexes were characterized by melting point, elemental analysis, FT-IR, thermal analysis and single crystal X-ray analysis. Complex (1) crystallizes in the triclinic space group P-1 and complex (2) in the rhombohedral space group R-3. The TGA analysis proves that complexes (1) and (2) undergo facile thermal decomposition at 550 degrees C to form copper titanium mixed metal oxides. The SEM/EDX and XRD analyses suggest the formation of carbonaceous impurity free good quality thin films of crystalline mixtures of beta-Cu(3)TiO(4) and TiO(2) for both (1) and (2), with average grain sizes of 0.29 and 0.74 microm, respectively. Formation of two different homogeneously dispersed oxide phases is also supported by electrical impedance measurements.

Heterobimetallic molecular precursors [Co2(acac)2mu-OH)2Cu4(dmae)4Cl4] (2) and [Ni2(acac)2(mu-OH)2Cu4(dmae)4Cl4] (3) [dmaeH = N,N-dimethylaminoethanol and acac = 2,4-pentanedionate] for the deposition of mixed oxide thin films were prepared by the interaction of tetrameric N,N-dimethylaminoethanolato copper(II) chloride, [Cu(dmae)Cl]4 (1) with M(acac)2.xH2O, [M = Co, Ni] in toluene. Both heterobimetallic cage complexes were characterized by melting point, elemental analysis, FT-IR spectroscopy, mass spectrometry, magnetometery, and single-crystal X-ray diffraction. Complexes 2 and 3 are isostructural and crystallize in the monoclinic space group P21/n. A TGA study shows that both complexes undergo controlled thermal decomposition at 450 degrees C to give mixed metal oxides. Solid-state infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and X-ray powder diffraction (XRD) analysis were performed to analyze the chemical composition and surface morphology of the deposited oxide thin films. The results obtained indicate the formation of impurity-free crystalline mixed oxide films with particle sizes ranging from 0.55 to 2.0 microm.

Ba(dmae)2 (dmaeH=N,N-dimethylaminoethanol, C4H11NO) reacts with Co(acac)2 (acac=2,4-pentanedionate) to produce the trinuclear coordination complex [Ba2Co(acac)4(dmae)3(dmaeH)] in an 85% yield. Spectroscopic and single-crystal X-ray diffraction experiments indicate that the complex possesses a structure in which two barium atoms and a cobalt atom are bridged by acac and dmae groups. The barium centers are eight and nine coordinate with BaO7N and BaO7N2 coordination spheres while the cobalt is a more regular CoO5N octahedron. This 2:1 heterobimetallic molecular complex was investigated as precursor for the deposition of thin film by AACVD. The film was characterized by SEM and XRD. TGA shows that the complex starts thermal decomposition upon heating in nitrogen atmosphere at 105 degrees C to produce barium cobalt oxide material of a Ba2CoO3 composition with an orthorhombic structure. The synthetic approach detailed here represents a unique route to the formation of a heterobimetallic barium cobalt coordination complex.

A simple method of depositing morphology- and phase-tailored thin films of copper(i) oxide and metallic copper from [Cu(dmae)(TFA)]4·CH2Cl2 (1), where dmae is N,N-dimethylaminoethanolato and TFA is trifluoroacetato, on glass substrates by aerosol-assisted chemical vapour deposition is demonstrated. The tetrameric precursor 1 was synthesized and its structure was determined by single-crystal X-ray crystallography. Precursor 1 was applied for the deposition of nanostructured thin films of copper(i) oxide and copper nanowires at 250 and 375°C respectively. The deposited thin films were characterized by powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray diffraction, and ultraviolet–visible spectroscopy. The results indicate that the phase and morphology of the deposited material are strongly dependent on deposition temperature. UV-vis studies reveal that copper(i) oxide films with a band gap of 2.48 eV may find possible applications in tandem photoelectrochemical devices as light-absorbing material.

The UVI atom in the title complex, [UO2(C5H7O2)2(C4H8O)], has a penta­gonal–bipyramidal geometry. The UVI atom is surrounded by seven O atoms, four of pentane-2,4-dione, one of the tetra­hydro­furan ligand and the two uranyl O atoms.

Heterobimetallic molecular Cu–Ni and Cu–Co complexes [Cu2Ni4(acac)2(dmae)2(dmaeH)2(OH)(TFA)6] (1) and [Cu2Co4(acac)2(dmae)2(dmaeH)2(OH)(TFA)6] (2) [dmae = N,N-dimethylaminoethanol, TFA = trifluoroacetic acid and acac = 2,4-pentanedionate] were prepared and tested as precursors for the deposition of mixed metal oxide composite thin films. The complexes were synthesized by reaction of the tetrameric copper(II) complex [Cu(dmae)(TFA)]4 with M(acac)2·xH2O [M = Ni, x = 2; Co, x = 1] in THF and were characterized by melting point, elemental analysis, FT-IR spectroscopy, TG/DTG and single-crystal X-ray diffraction. The complexes are isomorphous and crystallize in the triclinic centrosymmetric space group P. Aerosol assisted chemical vapour deposition (AACVD) studies carried out on (1) and (2) showed that they are promising precursors for the deposition of thin films of crystalline CuO–NiO and Cu2O–CoO composites, respectively. The size, shape, surface morphology, microstructure, chemical composition and crystallinity of the resulting mixed-metal oxide composite thin films were analysed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The analysis proved that the thin films are crystalline, uniform, smooth and tightly adherent to the substrates.

Heterobimetallic molecular precursors [Ba(dmap)4Cu4(OAc)6·THF] (1) and [Ba(dmap)4Cu4(TFA)6·THF] (2) [dmap = N,N-dimethylaminopropanolate, OAc = acetate and TFA = trifluoroacetate] for the deposition of barium–copper composite oxide thin films, were prepared by the interaction of Ba(dmap)2 with Cu(OAc)2 for 1 and Cu(TFA)2 for 2, in THF. Both heterobimetallic complexes were characterized by melting point, elemental analysis, FT-IR spectroscopy, mass spectrometry and single crystal X-ray diffraction. X-Ray crystallography shows that complex 1 crystallizes in the orthorhombic space groupP212121 with the cell dimensions a = 11.2621(11) A, b = 18.2768(17) A and c = 24.541(2) A, while complex 2 crystallizes in the monoclinic space groupC2/c with a = 23.9288(14) A, b = 19.8564(12) A, c = 25.5925(15) A and β = 112.4390(10)°. Thermal gravimetric analysis shows that both complexes 1 and 2 undergo controlled thermal decomposition at 450 °C and 400 °C, respectively, to give mixed metal oxide composite thin films. 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 BaCuO2–CuO composites from both 1 and 2, with average grain sizes of 105 to 175 nm and 110 to 205 nm, respectively.