Nanogenerators to Power Implantable Medical Systems

Replacing implantable medical devices (IMDs) is essential for their continuous operation, for which surgery is inevitable. Nanogenerators ( NGs) have gained attention as potential power solutions owing to their compactness and safety compared with electromagnetic field-based energy transfer technologies. Their working principle, which involves the generation of electrical potential from body movement, is suitable for sustaining IMDs' instant monitoring and sensor capabilities inside the body. In this regard, NGs hold promise for realizing self-powered IMDs that consume low power. For devices demanding a certain level of power required to operate sustainably, the realization of a powering system driven only by internal biomechanical energy has faced obstacles. Ultrasound referring to external mechanical energy has been found to have potential to noninvasively power IMDs that require relatively greater energy. This perspective discusses current NGs that are capable of coping with the IMDs' power demand and thereof driven IMDs application. This paper also focuses on recent advances in ultrasound-driven NGs and their future opportunities and strategies to be a competitive powering device for IMDs.