Partially metallized ITO electrodes serve as transparent and foldable conducting substrates

Abstract

Indium tin oxide (ITO) electrodes are widely used in flexible electronic devices such as touch panels, light-emitting diodes, solar cells, etc. However, it is known that when ITO electrodes are operated as cathodes in a humid atmosphere, their transparency and conductivity deteriorate due to reduction reactions. In this study, we discovered that by using the opposite approach—further promoting the very reduction reaction that should be suppressed—the ITO transparent electrode transforms into metallized ITO with high reflectivity and high conductivity. Furthermore, the partially metallized ITO electrodes along fold lines enabled them to be used as flexible and transparent substrates that suppress conductivity deterioration owing to cracks even after repeated folding.