Morphology Control And Properties Of Inorganic Semiconductor Nanomaterial (PbWO₄/PbO₂)

In the past few years, the materials with nanometer scale have attracted much interest owing to their potential application in optical, conductive/superconductive, catalytic and biological applications. Therefore, controlled fabrication of nanomaterials with different morphologies and architectures is always the study focus for scientists. This paper aimed to explore and study on the preparation of inorganic semiconductor nanomaterial. Several easy, facile techniques have been developed. By systematical adjusting the crucial factors in the reaction system, PbWO₄ and PbO₂ crystals with controllable morphology have been synthesized. The possible formation mechanisms and photoluminescent properties of PbWO₄ crystals have also been discussed.The main points are summarized as follows:1. In an ethanol/water mixed solvent, PbWO₄ crystals with various sizes and shapes have been synthesized in the presence of sodium dodecyl benzene sulfonate (SDBS) at room temperature. The influence of the experimental parameters including the ethanol/water volume ratio, the SDBS amount, the amount of reactants and pH value for morphologies of products were studied. The possible mechanism for the formation of lathlike PbWO₄ crystals was discussed. Photoluminescent properties of products were also investigated.2. In an ethylene glycol/water mixed solvent, the PbWO₄ crystals have been synthesized in the presence of SDBS at room temperature. The influence of the experimental parameters including the molar ratio of [Pb²⁺]/[WO₄^2-], the ethylene glycol /water volume ratio, the amount of reactants and pH value for morphologies of PbWO₄ crystals were studied. Photoluminescent properties of products were also discussed.3. PbWO₄ dendritic crystals have been prepared in O/W microemulsion containing SDBS, chloroform, n-butyl alcohol and aqueous solution. At the pH value of 10, cross-like crystals were prepared, and the possible mechanism was discussed.4. Various morphologies of PbO₂ crystals, such as nanoparticles, nanorods, microspheres consisted of particles have been prepared by low temperature solid-state redox reaction, liquid-phase oxidation and hydrothermal method.