Synthesis And Characterization Of Metal Sulfide Nanostructures

Semiconductor nanomaterials have attracted extensive attention due to their distinguished optical and electronic properties. Metal chalcogenides are important narrow-gap semiconductor materials, especially that the one-dimensional metal sulfides have been widely used in diverse areas, because of their excellent nonlinear optical properties, luminescence properties, quantum size effect and other important physical and chemical properties. In this paper, several typical metal sulfides were synthesized and their growth mechanisms and properties were discussed. The main contents were described as follows:1.Solvolthermal synthesis and formation mechanism of Bi2S3 nanorodsBi2S3 nanorods have been successfully synthesized by solvolthermal method using Bi nanoparticles as precursor in ethylenediamine-water system. The results show that the as-synthesized Bi2S3 nanorods belong to orthorhombic crystal system, with a preferential growth direction along the [002] direction. The diameter and length of the nanorods are 40~60 nm and 1~2μm, respectively. The influences of the solvent, pH value and the dosage of Na2S2O3 on the morphologies of the resulting products have been investigated. In addition, the growth process and formation mechanism of Bi2S3 nanorods was investigated by charactering the samples synthesized at various stages of the sovolthermal process.2.Hydrothermal synthesis and characterization of hexagonal CuS nanoplates Hexagonal CuS nanoplates have been synthesized by hydrothermal method with reactant of CuCl2·2H2O and Na2S·9H2O in the presence of cation surfactant cetyltrimethylammonium bromide (CTAB). The thickness and edge length of the nanoplates are about 15 nm and 60~70 nm, respectively. It belongs to hexagonal crystal system. The results show that reaction time and the add of CTAB play an important role in the fabrication of CuS nanoplates.3.Synthesis and of formation mechanism of CuS nanoflowersCuS nanoflowers have been synthesized by a facile solution-phase method in the mixture of CuCl2 and Na2S2O3 solution. The growth process of intermediate product was in-situ observed by TV microscopy. Then the formation mechanism of the as-synthesized CuS nanostructure were discussed, which indicated that the process involved four steps: complexation-decomposition- precipitation- aggregation.4.Synthesis and of formation mechanism of SnS nanostructureSnS nanorods with diameter of 60~80 nm and length up to 500~800 nm have been synthesized on a large scale under ethylene glycol solvothermal conditions with reactant of Na2S·9H2O and SnCl2·2H2O. SAED analysis reveals that the nanorods were single crystalline and grew along the [001] direction. The results show that the morphologies and structures of products gradually changed during the reaction, and finally evolved into belt-like SnS nanocrystal. In addition, the formation mechanism of SnS nanorods synthesized via a solution-phase method using sodium citrate as complexing agent were also studied.