摘要
采用stober法在乙醇介质中合成S iO2微球,将制得的样品在30℃下用双氧水浸泡处理48 h。扫描电子显微镜(SEM)测定结果表明,样品平均粒径为292 nm,平均标准偏差小于5%。傅里叶红外光谱(FTIR)测定表明,经双氧水浸泡处理后,S iO2微球表面的羟基数目增多。Zeta电位和标准氢氧化钠滴定测试结果显示,经双氧水浸泡处理后,S iO2微球在水溶液中的Zeta电位从-55.72 mV提高到-63.26 mV,表面电荷密度从0.19 uC/cm2提高到0.28 uC/cm2。用垂直沉积法制备出有序性较好的密排结构的S iO2胶体晶体。在SEM下,观察到这种胶体晶体是面心立方(fcc)密排结构,其(111)晶面平行于基底。透射光谱表明,所制备的胶体晶体在(111)方向具有光子晶体的带隙性质。
Colloidal SiO2 spheres were synthesized by hydrolysis of tetraethyl orthosilicate （TEOS） in the presence of water and ammonia in an alcoholic medium. In order to enhance surface charges of SiO2 spheres,they were immersed into H2O2 solution for 48 h at 30 %. SEM shows that the average size of SiO2 colloidal spheres is 292 nm,with standard deviation less than 5%. FTIR results indicate that the hydroxyl group on the surface of SiO2 spheres has increased through immersing into H2O2 solution. Zeta potential of the treated SiO2 spheres in water solution is improved from -55.72 mV to -63.26 mV, while surface charge density of the treated SiO2 spheres is enhanced from 0. 19 uC/cm^2 to 0. 28 uC/ cm^2. SiO2 colloidal crystal was fabricated from aqueous colloidal solution by vertical deposition method at 40 % and 60% relative humidity. SEM images reveal that the SiO2 colloidal crystal has facecentered-cubic （fcc） structure with its （111） planes parallel to the substrate. Transmission measurement shows the existence of photonic band-gap.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2006年第12期1151-1154,共4页
Fine Chemicals
基金
国家自然科学基金资助项目(50372038)~~
关键词
光子晶体
带隙
胶体晶体
垂直沉积法
SIO2微球
表面电荷密度
photonic crystals
band-gap
colloidal crystals
vertical deposition method
SiO2 colloidal spheres
surface charge density
