| Semiconductor nanomaterials exhibit unique optical, electrical, photoelectric conversion and catalytic properties due to its special structure, which endow them high value and broad application prospects in relevant fields. As important ?A-?A group semiconductor materials with highly anisotropic layered structure, bismuth sulfide and antimony sulfide have a wide energy gap covering the whole solar spectrum in room temperature that give them fine photoelectric, thermalelectric,catalytic performance and have extensive application in photodiodes, solar cells,photocatalyst and so on. Nanocrystallization makes their properties more excellent and applications broader. In consideration of substantial connection between performance and morphology, it is of great significants to achieve the controllable synthesis of nano bismuth sulfide and antimony sulfide with various morphologies.Thus, we investigate the influences of reaction condition on morphology and the electrochemical property of antimony sulfide nanomaterials.Bismuth sulfide and antimony sulfide nanomaterials with different morphologies are prepared by solvothermal and microwave irradiation methods successfully and the effection of reaction time, temperature, reactant ratio, the kind of sulfur sources and solvents on morphology are studied via changing reaction parameters during solvothermal and microwave irradiation process respectively. Moreover, the electrochemical properties of as-prepared nano antimony sulfide and the compositions of antimony sulfide and carbon are tested. The major works can be summarized as follows:First, the preparation of bismuth sulfide nanomaterials under solvothermal condition. Bismuth trichloride and thiourea are employed as bismuth and sulfur source respectively and the three-dimensional(3-D) bismuth sulfide nanoflowers are prepared successfully in acetone system. The influences of reaction time, temperature and the ratios of bismuth and sulfur on the morphology are discussed and it is found that the optimal condition to obtain 3-D bismuth sulfide well-nanoflowers is Bi : S =1:5, 150 ?, 16 h. Besides, the influences of the kind of solvents and sulfur sources are investigated and the results indicate that the 1-D bismuth sulfide nanostructures with higher aspect ratio are easier to be obtained in the solvent with lower viscosity and surface tension and the uniform nanorods are inclined to inform with employing rhodanine as sulfur source.Second, the preparation of antimony sulfide nanomaterials under microwave irradiation condition. The amorphous spherical antimony sulfide nanoparticles are synthesized in ethanol system with empolying antimony trichloride, thioacetamide(TAA) as antimony and sulfur source, then are translated into orthorhombic antimony sulfide single crystal nanostructures. We can find from this study that the reaction parameters including irradiation time, the kind of solvents and sulfur sources have significant impacts on the morphology of antimony sulfide nanomaterials, while the ratios of antimony and sulfur have little impact. In addition, the solvothermal treatment can translate the amorphous spherical antimony sulfide nanoparticles into orthorhombic phase bundle-like antimony sulfide nanostructures, but it seems that the solvothermal temperature have no obvious influence on the morphology.Third, the synthesis of antimony sulfide nanorods and the compositions of antimony sulfide and carbon composite nanomaterials and their electrochemical charging-discharging properties. The antimony sulfide nanorods with a diameter of50~100 nm and length of 5 ?m are prepared from antimony trichloride and sodium sulfide nonahydrate in ethylene glycol at 200 ? for 10 h. Subsequently, the compositions of antimony sulfide and carbon A and B are synthesized via a two-step method based on as-prepared antimony sulfide nanorods and one-step method respectively, and their charging-discharging performances as lithium battery anode materials are tested in a current density of 100 m A·g-1. There are no obvious change in the morphology among the three kinds of antimony sulfide-based nanomaterials.However, the composite materials, especially, B has a great improvement in the initial charging-discharging specific capacity, capacity reteintion and reversible capacity.The initial charging/discharging specific capacities of antimony sulfide, A and B are192.9/627 m Ah·g-1, 219.6/683.9 m Ah·g-1and 257.2/911 m Ah·g-1 respectively. And the coulombic efficiencies of both A and B are over 95 % after the second cycle. |
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