Research Progress of Silver Nanowires and Transparent Conductive Films
ZHOU Yangzhou1, QIAN Lei2, ZHANG Ting1,
1 School of Optoelectronics, Beijing Institute of Technology, Beijing 100081, China 2 Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, China
Abstract: In recent years, the transparent conductive films with high conductivity are widely used in optoelectronic devices. They are the important components of touch display, organic light emitting diode (OLED), thin film solar cells and the like. At present, indium tin oxide (ITO) as a transparent electrode plays a monopoly role in flat panel display and various electronic equipment applications, however, ITO itself has some shortcomings such as brittleness of ceramics, vulnerability to bending and damage, high preparation cost, high reaction temperature and yellowing, which seriously hinder the development of electronic devices towards miniaturization and flexibility. Therefore, a new conductive material is urgently needed to replace ITO and applied to flexible devices. The transparent conductive film based on silver nanowires (AgNWs) will become the most potential substitute for ITO conductive film due to its good transmittance, high conductivity, low cost and flexible bendability. In the past few years, the fabrication process and device structure of transparent conductive films based on AgNWs have been continuously optimized, which has attracted more and more attention of researchers. The aspect ratio of the AgNWs and the viscosity of the conductive dispersion directly affect the optical and electrical properties of the transparent conductive film. For AgNWs with high aspect ratio, only a small number of AgNWs is needed to build a highly conductive AgNWs network. The scattering of the prepared film layer can be effectively reduced, and its permeability can be greatly improved. The AgNWs dispersion is another non-negligible factor affecting the AgNWs conductive film. The dispersion and viscosity of the conductive dispersion directly affects the uniformity of the film. Therefore, obtaining high performance dispersion is the key to prepare AgNWs transparent conductive film. In addition, since the contact resistance between the AgNWs is huge, causing the sheet resistance of the prepared conductive film is also extremely large, so a corresponding post-treatment process of the film is required to reduce the square resistance of the film. In this paper, the synthesis methods of AgNWs at home and abroad are summarized. The research progress of AgNWs transparent conductive silver films in dispersion preparation, film preparation and post-treatment is summarized. The application of AgNWs transparent conductive silver films in optoelectronic devices is also described. Finally, the development trend of AgNWs flexible transparent conductive film in the future is prospected in order to provide reference for the preparation of high performance AgNWs transparent conductive film.