多元醇法合成银纳米线.ppt

1.The applications of silver nanowires 2.Introduction to synthesis of silver nanowires Approaches for synthesis of silver nanowires generally fall into one of two categories: Template-directed Templates including porous alumina membranes, carbon nanotubes, DNA chains, rod-shaped micells…… Template-free Wet chemical methods, vapor-phase synthesis…… 3.2 Mechanism 3.2 Mechanism (Cont.) References * Synthesis of Silver Nanowires Based on the Polyol Method 第七组： 王川? ? 邵乐 ?? 殷杰? ? 吴斌 ? ? 刘新玲? 多元醇法合成银纳米线 Synthesis of Silver Nanowires Based on the Polyol Method Outline: The applications of silver nanowires Introduction to synthesis of silver nanowires Synthesis of silver nanowires based on the polyol method 3.1 Introduction to the polyol method 3.2 Mechanism 3.3 Improvements of the polyol method 3.4 Further research Due to some unique properties，including high electrical and thermal conductivities, silver nanowires can be used as: Optical polarizers(偏光器） Photonic crystals（光学晶体） Biomdeidcal and chemical sensor Catalysts …… Jie Yao, et al.Science,2008,321,930 Silver nanowires rafts for trace analysis Optical negative refraction EG (ethylene glycol 乙二醇) AgNO3 PVP( polyvinylpyrrolidone 聚乙烯吡咯烷酮) Injected using a two-channel syringe pump at a rate of 0.3 mL/min 3.1 Introduction to polyol method The mixture stirred and refluxed at 160°for 60 min Separation by centrifugation, Purification Ag nanowires Yugang Sun, et al. Adv. Mater.,2002,14,833-836 I: Reduction II: Nucleation of seeds III: Heterogeneous nucleation and Crystal growth Yugang Sun, et al. Nano Lett.,2003,3(7):955-959 EG Serve as both reducing agent and solvent I: Reduction CH2OHCH2OH→ CH3CHO+H2O 2Ag+ +CH3CHO → 2Ag0+CH3COCOCH3+2H+ 3.2 Mechanism (Cont.) I: Reduction II: Nucleation of seeds III: Heterogeneous nucleation and Crystal growth II: Nucleation of seeds MTPs (multiply twinned particles 多