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Herein, we report the in situ single-step hydrothermal synthesis of hierarchical 2D SnS@ZnIn 2 S 4 nanoheterostructures and the examination of their photocatalytic activity towards hydrogen generation from H 2 S and water under sunlight. The photoactive sulfides rationally integrate via strong electrostatic interactions between ZnIn 2 S 4 and SnS with two-dimensional ultrathin subunits, i.e. nanopetals. The morphological study of nano-heterostructures revealed that the hierarchical marigold flower-like structure is self-assembled via the nanopetals of ZnIn 2 S 4 with few layers of SnS nanopetals. Surprisingly, it also showed that the SnS nanopetals with a thickness of $25 nm couple in situ with the nanopetals of ZnIn 2 S 4 with a thickness of $25 nm to form a marigold flower-like assembly with intimate contact.Considering the unique band gap (2.0-2.4 eV) of this SnS@ZnIn 2 S 4 , photocatalytic hydrogen generation from water and H 2 S was performed under sunlight. SnS@ZnIn 2 S 4 exhibits enhanced hydrogen evolution, i.e. 650 mmol h À1 g À1 from water and 6429 mmol h À1 g À1 from H 2 S, which is much higher compared to that of pure ZnIn 2 S 4 and SnS. More significantly, the enhancement in hydrogen generation is 1.6-2 times more for H 2 S splitting and 6 times more for water splitting. SnS@ZnIn 2 S 4 forms type I band alignment, which accelerates charge separation during the surface reaction. Additionally, this has been provoked by the nanostructuring of the materials. Due to the nano-heterostructure with hierarchical morphology, the surface defects increased which ultimately suppresses the recombination of the electron-hole pair. The above-mentioned facts demonstrate a significant improvement in the interface electron transfer kinetics due to such a unique 2D nano-heterostructure semiconductor which is responsible for a higher photocatalytic activity.Scheme 2 Schematic of the photocatalytic mechanism of SnS@ZnIn 2 S 4 heterostructures.This journal is

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Mn (II) and Fe(II) complexes with Schiff bases substituted salicyloyl pyrazole oximes were synthesized by the reaction of CFPHMP, FPHMP, DCFPHMP, CFPHMMP and BFPHMP (see introduction for definitions) with transition metal ion Manganese (Mn 2+ ) and Iron (Fe 2+ ). They were characterized by analytical and spectral methods. The elemental analysis data reveal that the Schiff base metal (II) complexes have 1:2 (M:L) stoichiometry. The molar conductivity data showed them to be non electrolytes. The Schiff bases are bidentate coordinating through the imine nitrogen and phenolic oxygen of salicyloyl pyrazole oximes. Based on analytical and spectral data, four-coordinate geometry is assigned for all complexes. The electronic absorption spectra suqqests the square planer geometry for the complexes. The ligand salicyloyl pyrazole oximes and their Mn (II) and Fe (II) complexes were screened against bacillus subtilis, Staphylococus aureus, actinomycetes and pseudomonas.