Recent progress in silver nanowire networks for flexible organic electronics

Recently, flexible transparent electrodes (FTEs) have attracted extensive attention as an essential element for future organic electronics (OEs), i.e. solution-processable, scalable and flexible organic electronics (FOEs). Although the traditional transparent electrode indium tin oxide (ITO) has been widely used in OEs, its brittleness and high cost significantly limit its application in the next generation of devices, typically flexible electronics. Thus, many alternatives, such as graphene, carbon nanotubes, conductive polymers, metal nanowires, metal grids and electrospun metallic nanofibers, have arisen at the forefront of FTEs. Among them, silver nanowire (AgNW) networks have attracted particular attention due to their excellent electrical conductivity and high transmittance, as well as facile availability and low cost. Since many studies on AgNWs have been published, a comprehensive review highlighting the advantages of AgNWs in FOEs is highly required. In this review, the synthesis and film fabrication of AgNWs have been firstly summarized, focusing especially on the properties of conductivity and light transmittance. Next, post treatments with different approaches to improve the conductivity of AgNWs have been included. And then, characterization of FTEs has been introduced with details on key parameters for FOEs. Furthermore, AgNW-based FOEs have been summarized to demonstrate the recent progress, such as organic light-emitting diodes (OLEDs), organic solar cells (OSCs), light-emitting electrochemical cells (LECs), organic field effect transistors (OFETs), organic memory devices (OMDs), etc. Finally, perspectives for AgNWs in FOEs have been discussed and concluded as well. It is expected that AgNWs could be the focus of future FOEs compared with other alternatives in terms of their advantages of optoelectronic properties, film-formation, solution-processability and flexibility. Silver nanowires for flexible organic electronics have been comprehensively summarized from synthesis, film fabrication, characterization and applications to perspectives.