Controllable Synthesis Of Silver Nanowires And Its Oxidation Atmosphere

Flexible electronics（FEs）are changing the way of our daily lifestyles recently and shown great developing potentials and marketing space in flat-panel displays,touch screen sensors,organic light emitting diodes based lighting and displays,electronic-paper displays,transparent electrodes and so on.Transparent conducting films（TCFs）are believed to be the key technology of FEs.Compared with traditional transparent and conductive indium tin oxide（ITO）and recently developed alternatives to ITO,nanostructured silver materials possessing superior electronic and heat conducting properties as well as low sintering temperature have been widely prepared for the fabrication of conductive networks.Among them,silver nanowires（AgNWs）have been recognized as one of the most promising solution-processible candidates for the fabrication of TCFs with large area,which could be achieved via industrial techniques such as paint spreading or sintering processes.In this thesis,AgNWs were taken as the research object and the ethylene glycol thermal reduction method was used to realize the controllable synthesis of AgNWs by optimizing the reaction conditions,and to explore the influence of oxidative atmosphere during the synthesis of AgNWs.The following experiments were mainly carried out:Firstly,the effects of various experimental parameters including temperature and the molar ratio of PVP to Ag NO₃ in preparing AgNWs were systematically investigated.At 160℃,increasing the molar ratio of PVP to Ag NO₃ was conducive to the reduction of the diameters of AgNWs down to 25 nm.At 125℃,the growth rate of AgNWs could be slow down at lower temperature.Consequently,the length of AgNWs could be prolonged and AgNWs with length up to 40μm and an aspect ratio beyond 1300 could be obtained.Secondly,by substituting Ag NO₃with CF₃COOAg and tuning the amount of H₂O₂ added to replace the oxidative effect of nitric acid,AgNWs with an average diameter of 40 nm and length up to 15μm were prepared under optimized reaction time.This verifies the oxidative effect of nitrate is beneficial for the selective retaining of twin structured seeds in the nucleation stage and controls the growth rate of AgNWs in the growth stage.