Biodegradable and High-Efficiency Ultraflexible Organic Light-Emitting Diodes Based on Cross-Linked PVA Substrates

Biodegradable organic light-emitting diodes (OLEDs) have attracted considerable interest due to their potential applications in eco-friendly electronics, novel implantable devices and degradable flexible displays. However, meeting the requirements of controlled biodegradation, high efficiency and operational stability of OLEDs at the same time is still a significant challenge, because most reported biodegradable substrates contain polar hydrophilic hydroxyl groups and have high roughness. Here, for the first time, we propose a cross-linking strategy as a biodegradable substrate for OLEDs to eliminate the hydrophilic group thereby improving the operational stability of the device. Moreover, ultrathin device (780 nm) illustrates a maximum current efficiency (CE) of 70.6 cd/A and external quantum efficiency (EQE) of 20.3%, which is superior to reported biodegradable OLEDs. This work extends a new strategy for achieving high-efficiency and biodegradable ultraflexible OLEDs, advancing the process of green ultraflexible displays in practical applications.