Advances in Flexible Metallic Transparent Electrodes

International audienceTransparent electrodes (TEs) are pivotal components in many modern devices such as solar cells, light-emitting diodes, touch screens, wearable electronic devices, smart windows, or transparent heaters. Recently, the high demand for flexibility and low cost in TEs requires a new class of transparent conductive materials (TCMs) as substitutes for conventional indium tin oxide (ITO), which is so far the most used TCM but exhibits brittleness and high cost. Among the different emerging alternative materials to ITO, metallic nanomaterials have received much interest due to their remarkable optical-electrical properties, low cost, ease of manufacturing, flexibility, and widespread applicability. These involve metal grids, thin oxide/metal/oxide multilayers, metal nanowire percolating networks, or nanocomposites based on metallic nanostructures. In this review, a comparison between TCMs based on metallic nanomaterials and other TCM technologies is discussed. Next, the different types of metalbased TCMs developed so far and the fabrication technologies used are presented. Then, the challenges that these TCMs face towards integration in functional devices are discussed. Finally, the various fields in which metal-based TCMs have been successfully applied as well as emerging and potential applications are summarized