Current cardiovascular implantable electronic devices (CIEDs) face a pressing clinical need for the development of battery-free, biodegradable, and biocompatible devices to mitigate the risk of adverse in vivo responses. To address this demand, it is proposed utilizing a natural biomaterial, silk sericin (SS), which exhibits valuable biological activities and contains abundant asymmetric amino acids with adjustable structures, to create an implantable self-powered system based on the piezoelectric principle. The functionalized SS-based (F-SS-based) piezoelectric film demonstrates a high longitudinal piezoelectric tensor (d