Long‐Lifetime Polymer Light‐Emitting Electrochemical Cells

Polymer light-emitting electrochemical cells with long operating lifetimes (see figure) are reported. The ions inside the luminescent semiconducting polymer are spatially redistributed by applying a voltage at a temperature above the melting point of the ionic liquid. These ionic-liquid-based light-emitting electrochemical cells also exhibit excellent current-rectification diode properties, a single-phase active layer, and short response times.