制备ZnO晶须的影响因素及其紫外吸收性能

Influence factors in preparing ZnO whiskers and ultraviolet absorption performance

在高碱度条件下,以Zn Cl2和Na OH为主要原料,氟碳类表面活性剂FC-NO1为表面活性剂,采用低温液相恒温陈化法制备针状ZnO晶须。采用X线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、能谱仪(EDS)和紫外-可见分光光度计(UV-Vis)对ZnO晶须的结构、物相组成、形貌及紫外吸收能力进行表征。考察反应物料配比、Zn2+浓度、陈化温度及陈化时间对制备针状ZnO晶须的影响,并初步探讨针状ZnO晶须的成核和生长机制。结果表明:制备针状ZnO晶须的优化条件为初始浓度0.2~0.3 mol/L,反应物料配比c(Zn^(2+))∶c(OH-)=1∶7,陈化温度85℃,陈化时间5 h。在最优条件下制得了形貌良好、结晶完全、纯度较高、长径比为15左右的针状ZnO晶须。UV-Vis吸收光谱显示产物在整个紫外波段有很强的吸收能力,且出现了轻微的蓝移现象。

Under the condition of high alkalinity,ZnO whiskers were prepared from zinc salt aqueous solution at low temperature with ZnCl_2 and Na OH as the main raw materials,FC-NO1 as surfactant. The structure,phase composition,morphology,and ultraviolet absorption capacity of ZnO whiskers were investigated by X-ray diffraction（ XRD）,field-emission scanning electron microscopy（ FESEM）,energydispersive spectrometer（ EDS）,and ultraviolet-visible spectrophotometer（ UV-Vis）,while the influences of reaction material ratio,Zn^（2＋） concentration,aging temperature and aging time on the needle-like ZnO whiskers were investigated,and the nucleation and the growth mechanism of ZnO whiskers were discussed. Results showed that the optimized conditions for preparing needle-like ZnO whisker were the initial concentration of zinc ions of 0. 2-0. 3 mol / L,the ratio of c（ Zn^（2＋）） to∶ c（ OH-） of 1-7,the aging temperature of 85 ℃ and aging time of 5 h. Under the optimal conditions,needle-like ZnO whiskers with good morphology,complete crystallization and high purity were prepared with its length to diameter ratio about 15. The UV-Vis absorption spectra showed that the product in the ultraviolet band had strong absorption ability with little blue shift.