Innovative Substrate-Free ACEL Devices Using Silver Nanowires: Addressing Environmental Impact, Enhancing Longevity, and Improving Mechanical Flexibility

The inevitable reliance on polymer substrates in conventional flexible alternating current electroluminescent (ACEL) devices, especially polyimide (PI) and poly(ethylene terephthalate) (PET), brings a dual challenge of environmental pollution and compromised device longevity due to insufficient heat dissipation. In response, this study presents an innovative substrate-free ACEL device featuring a top-emission structure. Utilizing Ag nanowires-based transparent electrodes, which allow for efficient heat dissipation into the ambient environment without the constraints of polymer substrate limitations, these devices demonstrate extended operational lifespans (up to 60 h) in contrast to those using PI (<2 h) and PET (<3 h) substrates, and achieve a maximum illuminance of 558 lx at approximately 8 cm from the center of the luminescent area (@130 V and 1 kHz). Furthermore, owing to the superior mechanical flexibility stability of the Ag nanowires-based electrodes and the absence of a substrate, the device exhibits merely 7% illumination degradation after 2000 bending deformations with a bending radius of 0.5 mm. This exceptional mechanical flexibility allows the device to conformally fit to intricate geometries, expanding its applicability in decorative and functional contexts. By mitigating environmental concerns, enhancing lifespan, and improving mechanical flexibility, this research represents a significant advancement in the field of ACEL devices.