Polymer light-emitting electrochemical cells—Recent advances and future trends

Summary Polymer light-emitting electrochemical cells (PLECs) are electroluminescent devices whose operation involves both ionic and electronic charges. A key reaction in PLEC is the electrochemical doping of the light emitter, a luminescent polymer, which eventually leads to the formation of a light-emitting p–n or p–i–n junction in the interior of the cell. This review opens with a general introduction to the operating mechanism of PLECs. This is followed by a summary of key advancements in the field in the last 2 years. The focus of the review is on the chemical mapping and optical probing of the PLEC doping process and junction structures. The results showcased in this review provide a coherent picture of the PLEC operating mechanism and point in new research directions in both device applications and fundamental sciences of mixed ionic/electronic polymer conductors.