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Abstract: Nickel phosphide nanocrystals with various phases have been successfully synthesized via a simple solvothermal route at 180°C for 16h, employing nickel chloride and white phosphorus (WP) as starting reactants in the presence of sodium dodecylbenzene sulfonate (SDBS). X-ray powder diffraction (XRD) research showed that the pure Ni12P5 phase with a high yield could be obtained in an ethanol solution, and the pure Ni2P form was prepared in a mixed system with the volume ratio of water/ethanol of 10:10. Namely, the presence of water molecules induced the phase conversion of nickel phosphides. Furthermore, in order to investigate the correlation between properties and phases, as a case, the photocatalytic degradation abilities of two nickel phosphide phases for organic dyes were compared. [Copyright &y& Elsevier]

Abstract: In this paper, we report the successful synthesis of NiTiO3 microtubes constructed by nearly spherical nanoparticles via a simple solution-combusting method employing a mixture of ethanol and ethyleneglycol (V/V=60/40) as the solvent, nickel acetate as the nickel source, tetra-n-butyl titanate as the titanium source and oxygen gas in the atmosphere as the oxygen source. The as-obtained product was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS). The UV–vis absorption spectrum of the product showed two absorption peaks centered at 258.6 and 350.1nm, respectively. The Brunauer–Emmett–Teller (BET) surface area of the product was 14.06m2/g and the pore size distribution mainly located from 20 to 30nm. The photocatalytic degradation property of the product for organic dyes showed that the as-obtained porous NiTiO3 microtubes could strongly promote the degradation of organic dyes including Pyronine B, Safranine T and Fluorescein. [Copyright &y& Elsevier]

Abstract: In the present paper, we successfully prepared PbTe nanocrystals in a simple aqueous system via the hydrothermal route employing PbO, Te powders and N2H4·H2O as the starting reactants at 150°C for 14h. Some factors affecting the morphologies of the PbTe nanocrystals, such as the reaction temperature, time, the amount of NaOH, sorts of reductants and Pb2+ ion sources, were systematically investigated. Experimental results indicated that, under keeping the other experimental conditions constant: raising the reaction temperature, the shapes of the as-obtained PbTe hardly changed, while decreasing the temperature, some PbTe dendrites were obtained; the short reaction time availed to obtain cubes with a hole in the center of each face; more amounts of NaOH were favorable to the formation of regular PbTe nanocuboids. When NaBH4 was used as the reductant, a large amount of near spherical PbTe nanocrystals was produced; while NaH2PO2 was used, many PbTe crystals with hollow framework structures were obtained. When Pb(CH3COO)2 was used as the Pb2+ ion source, some dendrites made of many irregular particles were generated; while PbSO4 was employed, many PbTe nanocuboids were produced. A possible formation mechanism of PbTe nanocrystals was proposed based on the experimental results. [Copyright &y& Elsevier]

Abstract: In the current paper, we successfully prepared lead sulfide (PbS) microcrystals with various shapes in a simple aqueous system using the hydrothermal synthesis route. Experimental results indicated that the change of the molar ratio of Pb2+/S2O3 2− could significantly influence the morphology of the product while keeping the other experimental conditions constant: with the decrease of the molar ratio of Pb2+/S2O3 2− from 1:1 to 1:4, the shape of the products varied from tri-prism, cube to magic-square structure. Changing the reaction temperature had big effect on the shape of the product: flower-shaped product was obtained at 80°C and cube-shaped products were produced at 120°C. When the reaction time varied, the shapes of the as-obtained PbS crystals also changed. At the same time, SEM observations showed that the counter-anions for Pb2+ could influence the shape of the product: Pb(NO3)2 being used as lead ion sources, most flower-shaped and few cubic PbS crystals were produced; while PbSO4 as lead ion source, the PbS cubes were obtained. An evolution process was described based on experimental facts. [Copyright &y& Elsevier]