Waterproof and Wearable Power Sources

Wearable electronics can be effortlessly incorporated into human skin or fabrics for continuous physiological health monitoring. A reliable energy supply system is vital for ensuring the long-term operation of these devices. Ultraflexible organic photovoltaics have gained attention as a promising power source for wearable electronics due to their stretchable and lightweight characteristics. However, achieving waterproofing for ultraflexible organic electronics without compromising mechanical flexibility and conformability has been a considerable challenge. This study underscores advancements in the development of waterproof, ultra-flexible solar cells designed to power wearable electronics and sensors. We demonstrate the fabrication of waterproof, ultraflexible organic photovoltaics by employing in-situ growth of a hole-transporting layer, which enhances adhesion between the active layer and the anode. The resulting 3 μm-thick organic photovoltaics retain 89% and 96% of their initial performance after 4 hours of water immersion and after undergoing 300 stretching and releasing cycles at 30% strain underwater, respectively. Additionally, these ultraflexible devices withstand machine washing test with an exceptionally thin encapsulation layer, a feat not previously reported.