期刊論文

標題 Preparation of Nanowire Silica Inside Self-Assembled Sodium Bis(2-ethylhexyl) Sulfosuccinate (AOT) Gels
學年 105
學期 1
出版(發表)日期 2016/11/30
作品名稱 Preparation of Nanowire Silica Inside Self-Assembled Sodium Bis(2-ethylhexyl) Sulfosuccinate (AOT) Gels
作品名稱(其他語言)
著者 Wei-Chi Lai; Li-tzuen Hong
單位
出版者
著錄名稱、卷期、頁數 The Journal of Physical Chemistry B 120(37), p.10010–10017
摘要 In conventional sol–gel methods, gel formation occurs due to aggregation of particles into irregular shapes of larger size. In this study, we conducted hydrolysis–condensation reactions of tetraethyl orthosilicate (TEOS) within water-laden channels inside the space created by self-assembled AOT molecules to prepare regular and nanosized silica in self-assembled sodium bis(2-ethylhexyl) sulfosuccinate (AOT) gels. The AOT gels were obtained by adding small amounts of water to organic solvents containing high concentrations of AOT. Adding silica significantly influenced the rheological properties and microstructures of these AOT/silica gels. Rheological studies showed that the storage modulus G′ and loss modulus G″ of the AOT gel systems became very close and even crossed, indicating that the gel is “weak”; however, for the AOT/silica gel systems, the rheological data demonstrated that G′ is greater than G″ at all frequencies, indicative of a real gel with a G′ of approximately 105 pa. Small-angle X-ray scattering (SAXS) results showed that the gels initially had a hexagonal close-packed cylindrical structure with long-range order and transitioned to nonclose-packed cylindrical structures without long-range order as the silica formed. The cylinder is expected to comprise stacks of silica molecules surrounded by AOT molecules, and the radius of the cylinder is close to the sum of the length of one AOT molecule and half the size of one silica molecule. The rheological and SAXS data show that silica in the AOT/silica systems grew in the axial direction due to the confinement of these cylindrical structures, leading to nanowire silica structures. After removal of the AOT components, the nanowire silica was approximately 5–10 nm in diameter, as observed using transmission electron microscopy (TEM).
關鍵字
語言 英文(美國)
ISSN 1520-6106; 1520-5207
期刊性質 國外
收錄於 SCI;
產學合作
通訊作者
審稿制度
國別 美國
公開徵稿
出版型式 ,電子版,紙本