Powering the future of wearable electronics: integrated energy harvest and storage for self-sustaining systems

Driven by extensive research on materials design, manufacturing processes, and wearable applications, flexible electronics have emerged as a critical concern for next-generation electronic technologies. However, the demand for sustainable, integrated, and multi-functional flexible energy sources remains largely unmet. For wearable electronic devices, the development of flexible energy devices is crucial because they can seamlessly adapt to the dynamic deformation of the human body, ensuring wearing comfort while providing a continuous, stable, and reliable power source for the device. This review focuses on recent advancements in self-powered flexible devices, which integrate flexible energy-harvesting devices with flexible supercapacitors to construct all-in-one, self-powered systems. Firstly, the performance requirements of different types of flexible supercapacitors for flexible electronics are outlined. Subsequently, the development trend of building sustainable energy supply systems is discussed, where photovoltaic, thermoelectric, piezoelectric, and triboelectric devices are used as energy-harvesting units paired with flexible supercapacitors as energy storage units. Moreover, self-powered electronics for health monitoring, motion detection, self-healing, and electrochromism applications are summarised. Finally, we provide an overview of the development opportunities and prospects for self-powered electronic devices, outlining their rapid growth in the field of wearable electronics.