A kirigami-inspired island-chain design for wearable moistureproof perovskite solar cells with high stretchability and performance stability.

A range of power generating approaches, such as integration with clothing, fashion accessories, or textiles, allow electronic devices to be charged in environmentally friendly ways. Stretchable, efficient, stable, and even washable solar cells are considered the next necessary component to supply continuous wearable energy. However, ultra-thin photo-active materials are often fragile, which inevitably raises challenges for electron conduction during stretching and washing processes, thus resulting in unsatisfactory output performance. Herein, we have removed the stumbling block by designing a kirigami-inspired unique island-chain structure with serpentine interconnects, which prevented the photo-active layer of subcells from being subjected to excessive strain. Notably, this is the first time perovskite solar cell arrays met the above wearable requirements simultaneously. The obtained devices exhibited a high yet stable power output (efficiency of 17.68%) accompanied by a robust cycling performance (87% of the initial PCE) even after 300 times of continuous stretching with a large ratio of 80%. The efficiency of the optimized PSCs maintains promising stability after being exposed in a harsh environment (80% humidity) for 10 days. As textile-compatible power sources, the successfully designed stretchable and moisture-resistant photovoltaics add power-generation functionality to clothing, opening a new avenue for applications as long-term power sources for wearable electronics.