纳米结构V_2O_5空心微球的制备与表征

Fabrication and Characterization of Nanostructural Vanadium Pentoxide Hollow Microspheres

以自制的二乙酰丙酮氧钒(VO(aca)_2)为原料,通过软模板法组装出聚乙烯吡咯烷酮(PVP)/钒前驱体核壳结构的复合微球.对复合微球进行热处理后制备得(?)(0.5～1.0)μm五氧化二钒(V_2O_5)中空微球.分别采用扫描电镜(SEM)、透射电镜(TEM)和X射线衍射仪(XRD)对最终产物的球形外观、中空结构和物相组成进行了表征,结合VO(acac)_2、溶解于乙二醇的PVP、溶解于乙二醇的VO(aeac)_2与复合微球的红外光谱(FTIR)和复合微球的差热曲线(DTA),探讨了V_2O_5中空微球形成的机理.对影响实验的因素如PVP和VO(acac)_2的浓度,保温时间等进行了研究.结果表明:通过严格控制PVP和VO(acac)_2的浓度能够确保V_2O_5球壳结构的形成;当总反应时间在75～90min范围内时,所得空心球的几何外形和表面形貌均较为理想.

Polyvinylpyrrolidone（PVP）/vanadyl glycolate （VO（OCH2-CH2O）） core-shell microspheres were assembled by soft-templating method using vanadyl acetylacetone （VO（acac）2） as raw materials. And then vanadium pentoxide （V2O5） hollow spheres with particle size from 0.5 to 1μm were obtained by the calcination of composite microspheres. SEM, TEM and XRD were adopted to characterize the spherical morphology, hollow structure and phase composition of the final product, respectively. The mechanism of the formation of V2O5 hollow spheres was discussed based on the F TIR of VO（acac）2, PVP dissolved in EG, VO（acac）2 dissolved in EG, VO（OCH2-CH2O）/PVP microspheres and the DTA curve of composite microspheres. Effects of concentration of reagents, the time of reaction on the experiment were studied. The results indicate that the core-shell composite microspheres can be prepared through the precise control of the concentration of PVP and VO（acac）2, and the microspheres will be formed with ideal shape and surface morphology with reaction time ranging from 75min to 90min.