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Synthesis of 5-arylidine thiobarbituric acids containing different functional groups with variable electronic characters were described and their Co(2+), Ni(2+) and Cu(2+) complexes. The stereochemistry and mode of bonding of 5-(substituted benzylidine)-2-TBA complexes were achieved based on elemental analysis, spectral (UV-VIS, IR, (1)H NMR, MS), magnetic susceptibility and conductivity measurements. The ligands were of bidentate and tridentate bonding through S, N and O of pyrimidine nucleolus. All complexes were of octahedral configuration. The thermal data of the complexes pointed to their stability. The mechanism of the thermal decomposition is discussed. The thermodynamic parameters of the dissociation steps were evaluated and discussed., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Molybdenum Disulphide (MoS2) being an efficient photocatalyst due to its unique optical and structural properties, have attained the attention of researchers during last decade. However, poor absorption of light, fast recombination of charge carriers and low active sites are the barriers for its effective use as a photocatalyst. These constraints could be removed by the incorporation of transition metals in pure MoS2. To that end, we employed a facile and cost-effective hydrothermal method for preparation of pure and copper (Cu) doped (1, 3, 5, and 7%) MoS2 nanomaterials to investigate their degradation efficiency against methylene blue (MB) dye at different pH values (04–10) of reaction solution. Various characterization techniques like SEM, EDX, XRD, FTIR, UV–Vis, and PL were utilized to explore the morphological, compositional, structural, vibrational and optical properties of fabricated nanomaterials. The results revealed that 5% Cu doped MoS2 is an optimal sample among all other fabricated materials, having hexagonal structure, lowest band gap and recombination time of photogenerated charge carriers. This leads to its extraordinary performance in the degradation of MB (i.e.94%) in basic medium having pH 09. The outcomes of this research would be a valuable contribution toward advancing the development of exceptionally efficient TMDs photocatalysts for degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Copper-bismuth-sulfide (Cu 3 BiS 3) has gained great interest as solar cell absorber owing to the advantages of being cheap, abundant, and non-toxic. Fabrication of phase-pure and large-grain absorbers are desirable for their integration in solar cells. Herein, we have used a sequential evaporation and chalcogenization (350–450 o C) process to fabricate phase-pure and large-grain Cu 3 BiS 3 films. X-ray diffraction indicated a CuS secondary phase at 350 °C and single-phase Cu 3 BiS 3 at 400 and 450 °C in the sulfurized films. Elemental analysis revealed a near-stoichiometric Cu 3 BiS 3 composition for all the films. X-ray photoelectron spectroscopy was used to assess the valence states of elements. Microstructural analysis confirmed the formation of compact and large-grained Cu 3 BiS 3 films with an average grain size of 5 μm at 350 °C. The grain size decreased with increasing sulfurization temperature (400–450 °C). The direct bandgap decreases from 1.42 eV to 1.32 eV with increasing sulfurization temperature from 350 to 450 °C. Hall measurements indicated decreased electrical resistivity and increased hole mobility and carrier concentration with increasing the sulfurization temperature. From this study, the Cu 3 BiS 3 absorbers produced at 400 o C exhibited superior phase purity and good quality suitable for the solar cells. [Display omitted] • Fabrication of Cu 3 BiS 3 thin films by sequential evaporation and sulfurization. • Influence of sulfurization temperature on the Cu 3 BiS 3 film formation was studied. • Phase-pure and large-grained Cu 3 BiS 3 films were obtained at 400 and 450 °C. • Bandgap and resistivity of Cu 3 BiS 3 film decreases with increasing temperature. • Cu 3 BiS 3 films synthesized at 400 and 450 °C are suitable for solar cell fabrication. [ABSTRACT FROM AUTHOR]