Preparation And Electrochemical Performance Of SnS₂, SnO₂Hierarchical Flower-like Microsphere

SnS2and SnO2are important tin-based compounds and have excellentproperties of optical, catalytic, electrochemical, magnetic and gas sensing etc.,and have a wide range of applications in the fields of gas sensors, resistors,photoelectric detectors, photoconductive materials, luminescent materials,photocatalyst, Li-ion batteries, solar cells and so on. Inorganic functionalhierarchical structures integrated micro-nano-materials and nano-scale effectsarising from the combined effects makes it one of the hot research fields ofnano-materials and have great advantage in energy storage, catalysis, watertreatment, energy conversion. Therefore, it is important to develop simple,reliable soft synthesis method of hierarchical structures, and explore its newfeatures. With controlled reaction conditions, we successfully synthesized SnS2(SnO2) hierarchical structures, and systematically explored the key factor forpreparing hierarchical structures; and relationships of electrochemical propertyand structures, Including:1. Synthesis and electrochemical properties of SnS2flower-likemicrospheres by hydrothermal method assisted with L-cysteine.By adjusting the concentration and reaction temperature of L-cysteine,we successfully synthesized SnS2flower-like hierarchical structures.Studies have shown that in the initial reaction system, the concentration of S2-isthe key factor of SnS2hierarchical structures, crystallinity, assembled unit,assembled form of micro and nano structures. Meanwhile, the structures of SnS2also affect the Li-ion storage properties.2. Preparation and electrochemical properties of porous flower-like SnO2microspheres.The porous flower-like SnO2microspheres were obtained in air by calciningflower-like SnS2microspheres. Studies showed that the calcination temperatureand heating rate have great effect on the crystallization and structure of theproduct. SnO2flower microspheres not only keeped the hierarchical structure ofprecursor, but also produced abundant pore structures at the same time.Electrochemical tests showed that the flower-like hierarchical structures caneffectively buffer the volume change of lithium ion on deintercalation process,and showed improved cycling performance.