A Facile Route to Efficient, Low‐Cost Flexible Organic Light‐Emitting Diodes: Utilizing the High Refractive Index and Built‐In Scattering Properties of Industrial‐Grade PEN Substrates

Abstract

An industrial-grade polyethylene naphthalate (PEN) substrate is explored as a simple, cost-effective platform for high-efficiency organic light-emitting diodes (OLEDs). Its high refractive index, combined with the built-in scattering properties inherent to the industrial-grade version, allows for a significant enhancement in outcoupling without any extra structuring or special optical elements. Flexible, color-stable OLEDs with efficiency close to 100 lm W(-1) are demonstrated.