在有關向列型液晶中參雜膠體粒子(particle dispersed in liquid crystals)此主題的許多論文中，都發現了膠體粒子會於向列型液晶中表現出自發聚集的現象。然而，多數論文所使用的膠體粒子皆具有平滑表面，而具有粗糙表面的膠體粒子則甚少討論。因此，本論文引入一種新穎材料—中孔洞氧化矽球(mesoporous silica hollow sphere, 簡稱MPSHS)，其具有粗糙的表面和內部空腔。對於粗糙表面和向列型液晶分子的交互作用，我們提出無序層(disorder layer，簡稱DOL)的假設來描述圍繞中孔洞氧化矽球的液晶分子方向，並預測此無序層能夠抑制中孔洞氧化矽球在向列型液晶內自發聚集。
在本論文中，我們使用了三種工具來試圖驗證無序層的假設。三種工具分別為偏光顯微鏡、光鉗以及細菌偵測器。在偏光顯微鏡觀察下，我們確立中孔洞氧化矽球的粗糙表面對周圍的向列型液晶分子起到平面錨定的效果。而藉由光鉗的操作，我們測量兩顆中孔洞氧化矽球和兩顆表面有垂直配向的實心二氧化矽球(solid silica sphere，簡稱SSS)的吸引距離，發現了前者比後者低，由此間接證明無序層的存在。最後，我們試圖利用細菌偵測器，想得到更進一步有關無序層存在的直接證據。然而，從細菌偵測器遇到中孔洞氧化矽球表現出的推球行為裡，我們推測細菌偵測器在探測小膠體粒子周圍液晶分子方向的能力有限。

The self-assembling and aggregating behavior of colloidal particles in nematic liquid crystals have been reported in many papers for several years. Here, we introduced a new nematic colloid-LC system made of the mesoporous silica hollow sphere (MPSHS) which have a rough surface and a cavity. The disorder layer (DOL) postulate was proposed by us to describe the orientation of LC molecule surrounding MPSHS and predict the suppression of aggregated behavior of MPSHS in nematic LC. We try to prove the DOL postulate by using three tools: the polarized optical microscopy, the optical tweezer, and the bacterial detector. We report experimental studies on planar anchoring induced by the mesoporous surface of MPSHS which was observed by POM. By the assistance of optical tweezer, we found the lower attraction distance between two MPSHSs than two SSSs with homeotropic anchoring which provides the indirect proof on the existence of DOL. The bacteria detector shows the cargo-pushing behavior when it meets MPSHS imply the limited ability of it to detect the orientation of LC molecules around small colloids.

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