胶体粒子的自组装及应用.pptVIP

* Synthesis and assembly of structured colloidal particles J. Mater. Chem., 2008, 18, 2177-2190 Introduction Recently, non-spherical and non-isotropic spherical particles have been proposed as building blocks for non-conventional structures that may lead to better optical properties. Individual non-spherical particles can have interesting optical properties by themselves. Colloidal particles have been used as model systems for the study of molecular interactions and of atomic crystals. Categorized by the type of colloid: 1.Shape-anisotropic particles 2.Chemically patterned particles 3.Internally structured particles Fig. 1 Schematic diagram of shape-anisotropic, chemically patterned, and internally structured colloidal particles. 1. Shape-anisotropic particles Ellipsoidal particles Dumbbell-like particles Anisotropic particles with complex morphology Lithographically defined particles Colloidal clusters Ellipsoidal particles eg：Ho et al. PS +PVA -----水中混合------制膜------拉伸（高于玻璃化转变温度）------快速冷淬-----------溶解PVA Champion et al. modified the stretching method slightly Jiang et al. 制备椭球空穴的聚合物基质----填入无机颗粒------煅烧聚合物------椭球堆 其他方法：通过高能离子束照射无机颗粒 Fig. 3 SEM images of deformed silica particles after Xe ion irradiation at (a) 4 MeV and (b) 1 MeV. Reprinted with permission from ref. 9. Copyright 2003, American Institute of Physics. B.Dumbbell-like particles The use of swollen styrene monomers and crosslinking agents with cross-linked seed PS latex resulted in phase separation before polymerization occurred. The acceleration of phase separation during polymerization induced the formation of dumbbell particles. C.Anisotropic particles with complex morphology ice cream cone-like or popcorn-like particles The swelling and phase separation technique can be used for superparamagnetic coreshell particles with anisotropic shapes D.Lithographically defined particles E. Colloidal clusters 2. Chemically patterned colloidal particles 2011.10.14组会 Synthesis