双相分散聚乙烯吡咯烷酮包覆氧化锌纳米粒子的微乳液法制备,结构和光学性质

Synthesis of bi-phase dispersible polyvinylpyrrolidone-capped zinc oxide nano-particulate via emulsion route and its structure as well as optical property

以乙酰丙酮锌为前躯体、聚乙烯吡咯烷酮(PVP)为表面活性剂,采用纳米微乳液法制备了有机相和水相双分散PVP包覆氧化锌(PVP-ZnO)纳米粒子;采用X射线衍射仪、透射电镜、红外光谱仪分析了其相组成、微结构及化学特征,利用紫外-可见吸收光谱仪和荧光光谱仪测定了其光学性质.结果表明,制备的纳米ZnO具有六方纤锌矿结构,粒径分布范围窄,结晶性好.纳米ZnO表面包裹PVP,使得PVP-ZnO在无机和有机溶剂中皆具有很好的分散性.与此同时,PVP-ZnO纳米粒子在紫外区尤其是373 nm处显示很强的紫外吸收,而在380nm的激发光下在496nm左右产生强蓝绿光发射,并在587nm处伴有弱黄绿光发射.

Bi-phase dispersible ZnO nanoparticles surface-capped by polyvinylpyrrolidone（PVP） were prepared using nano-emulsion method in the presence of zinc acetylacetone[Zn（acac）_2]as the precursor and PVP as the surfactant.The phase composition,microstructure and chemical feature of resultant PVP-ZnO nanoparticles were analyzed by means of X-ray diffraction,transmission electron microscopy,and infrared spectrometry.Its optical properties were evaluated by means of ultraviolet-visible light absorbance spectrometry and florescence spectrometry.It has been found that as-synthesized PVP-ZnO nanoparticles have hexagonal structure and narrow size distribution as well as high crystallinity.Thanks to the encapsulation of nano-ZnO by PVP,PVP-ZnO nanoparticles are well dispersible in both organic and inorganic solvents.In the meantime,PVP-ZnO nanoparticles show a strong absorption band around 373 nm.Under an excitation at 380 nm,PVP-ZnO nanoparticles show strong blue-greenish emission peaks around 496 nm and weak emission peaks around 587 nm at room temperature.