Purification And Application Of Very Thin Silver Nanowires

Very thin silver nanowires(VTAgNWs)are ideal components for making high performance transparent conductive films(TCFs)simultaneously with a high visible light transparency,a small haze factor,a low sheet resistance and a high uniformity.However,nanoparticles contained in the product which relies on the polyol reduction of silver ions are unfavorable to the overall performance of TCFs,and there have been no cost-effectiveness and environment-friendliness methods to purify VTAgNWs.The purpose of this paper is to study the purification of VTAgNWs,proposes a simple,non-toxic and cheap way to purify VTAgNWs and prepares a transparent conductive film of VTAgNWs with excellent performance.The main results are as follows:1.Obtaining high-purity very thin silver nanowiresVTAgNWs with an average diameter of approximately 20 nm has been synthesized by the polyol reduction method in the presence of Br-and Cl-ions.We rely on the coarsening of the nanoparticles by Ostwald ripening-driven to improve the settling rate of particles.Sedimentation combined with brief filtration could effectively separate the particles from VTAgNW and remove almost all the impurities in the solution,including different ions,organic chemicals and nanoparticles of various size.According to sedimentation theory,the sedimentation effect could be further optimized by careful selecting the parameters of sedimentation,such as the solvent,the time duration,solute concentration and the container.This method is free from the entanglement of toxic acetone and could obtain high-purity VTAgNWs.And that,the operation is convenient and suitable for large-scale implementation.2.Preparing high-performance transparent conductive filmsThe films prepared with the purified VTAgNWs can achieve better performance than ITO without further treatment processes:sheet resistance of 71.3 ± 2.9 Ω/□,standard deviation of the sheet resistance of 4.0%,transmittance of 91.7%,and haze of 1.0%.Transparent conductive films prepared using purified very thin silver nanowires exhibit excellent optoelectric properties and meet the requirements of the high-end display applications such as touch panels and flat panel displays.