Solvothermal Preparation And Photoluminescence Properties Of PbS, PbSe Nanocrystals And Pbs/pbse Alloyed Heterostructures On Lead Substrates

It’s a hotspot in the field of nanoscience and technology that the research of electronics, optoelectronics and sensors nanodevice. Especially, enhanced photoelectric function of the semiconductor and heterogeneous structure material, which owned the special optical, electrical, and catalytic properties of nano/micro materials, is the key of preparing of nanoscale devices.Nanomaterials of lead chalcogenides (PbS, PbSe) have been studied extensively over the past decades owing to their unique chemical and physical properties and potential applications in nanoscale devices. PbS is an important semiconductor material with large exciton Bohr radius (18nm) and small band gap energy (0.41eV). The nonlinear optical properties of PbS nanoparticles are useful for optical devices such as infrared photovoltaics, infrared LED, and optical switches. PbSe is a narrow-gap Ⅳ-Ⅵ semiconductor, and also a promising material for many nanotechnology-related applications, for instance, thermoelectric coolers, infrared photodetectors, heat converter, solar cells with carrier multiplication. Semiconductor compound structure of each component has a different band gap and the dielectric constant. It can produce the new electronic level and band gap, and form a new electronic-hole composite center, change carriers composite path, when different band gap of semiconductor material compound and will show more higher, stronger function characteristics.In this paper, the PbS, PbSe semiconductors and PbS/PbSe alloy heterogeneous structure had been achieved on lead substrates directly by solvothermal method, with the aid of polyvinylpyrrolidone (PVP). The sublimed sulfur powder and selenium powder are sulfur source and source of selenium respectively. To emphasize, lead foil is not only as the carrier of products, but also as the source of lead. At the same time, we inspected the influence on the morphology of PbS and PbSe semiconductor materials by the kinds of solvents and surfactants. In order to study PbS and PbSe semiconductor material reaction process, we inquiried the reaction time and reaction temperature. The morphology, composition and structure of products were characterized by a variety of analysis methods. Finally, the room temperature emission spectra (PL) measurement was used to determining luminescence properties of the PbS, PbSe and PbS/PbSe alloyed heterostructure, which synthesized in hydrazine hydrate solvents.