Stretchable transparent electrodes for conformable wearable organic photovoltaic devices

To achieve adhesive and conformable wearable electronics, improving stretchable transparent electrode (STE) becomes an indispensable bottleneck needed to be addressed. Here, we adopt a nonuniform Young's modulus structure with silver nanowire (AgNW) and fabricate a STE layer. This layer possesses transparency of >88% over a wide spectrum range of 400-1000 nm, sheet resistance below 20 omega sq(-1), stretchability of up to 100%, enhanced mechanical robustness, low surface roughness, and good interfacial wettability for solution process. As a result of all these properties, the STE enables the fabrication of a highly efficient ultraflexible wearable device comprising of both organic photovoltaic (OPV) and organic photodetector (OPD) parts with high mechanical durability and conformability, for energy-harvesting and biomedical-sensing applications, respectively. This demonstrates the great potential of the integration of OPVs and OPDs, capable of harvesting energy independently for biomedical applications, paving the way to a future of independent conformable wearable OPV/OPDs for different applications.