Low-Cost, Organic Light-Emitting Electrochemical Cells with Mass-Producible Nanoimprinted Substrates Made Using Roll-to-Roll Methods

Next-generation, power-efficient organic lighting systems, which ideally would be low-cost and mass-producible, are urgently needed because more than 20% of total electricity use goes to lighting. This study presents polymer light-emitting electrochemical cells (PLECs) made using mass-producible nanoimprinted corrugated substrates, which effectively improve light extraction efficiency. The corrugated substrates are fabricated using roll-to-roll methods, using self-assembled block copolymers on glass and film substrates (glass: 0.45 m × 0.55 m, film: 0.6 m wide). Using the glass-type corrugated substrates, two PLECs based on (poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene]) and (“super-yellow” poly(p-phenylene vinylene)) (SY-PPV) are fabricated by solution-based spin-coating methods, which can in practice be replaced by roll-to-roll methods. The corrugated PLECs with SY-PPV show high brightness of 1740 cd cm⁻² and 2.1 times greater efficiency without changing the original spectrum or angular dependence. This successful combination of corrugated substrates and PLECs is one of the best examples of a promising cost-effective, high-performance lighting technology.