Piezo-supercapacitors: A new paradigm of self-powered wellbeing and biomedical devices

Piezoelectric supercapacitors (PSCs) constitute a type of emerging technology that can harvest and store energy simultaneously from natural processes, such as human body motions (breathing, walking, arm-motions, etc.) and waves, which makes them attractive for powering wearable and biomedical devices. However, designing such integrated devices requires in-depth understanding of the physical properties of the individual components, such as the piezoelectric and electrode materials. Herein, we explore the potential of PSCs in wellbeing and healthcare devices, covering key considerations on the electrode materials, electrolytes, and piezoelectric materials. The process of tuning the self-charging characteristics of PSCs with nanocarbons, metals oxides, and composite-based materials is outlined systematically. In addition to material integration, practical demonstrations of the PSCs converting energy from natural processes to operate various wearable and biomedical devices are discussed. Finally, the challenges and future directions for developing efficient PSCs for next-generation self-powered devices are presented.