Self-powered biomedical implants improve the life of patients and lower the risks associated with battery replacement. Piezoelectric energy harvesters that generate electricity from the cardiac motions are among the potential candidates to be used in self-powered implants, such as cardiac pacemakers. In this context, lead-based ceramic piezoelectric nanogenerators (PNGs) were emerged, which are toxic and susceptible to fatigue crack, causing harm to the patients. Polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE)-based films were also developed as cardiac energy harvesters. Here, we show a battery-free heart pacemaker that is powered by the generated electricity of a biocompatible and flexible piezoelectric polymer-based nanogenerator (PNG) from the cardiac motions of the left ventricle. The PNG is comprised of composite nanofibers of poly(vinylidene fluoride) (PVDF) and a hybrid nanofiller made of zinc oxide (ZnO) and reduced graphene oxide (rGO). The composite nanofiber is optimized towards achieving a large power output. In vivo implanted optimized PNG can successfully harvest 0.487 μJ from every heartbeat, which is conveniently larger than the pacing threshold energy for the human heart. The successful demonstration of a self-powered pacemaker places the polymer-based PNGs among the viable candidates for self-powered biomedical implants.

自供电的生物医学植入物可改善患者的生活，并降低更换电池的风险。通过心脏运动产生电能的压电能量收集器是可用于自供电植入物（例如心脏起搏器）的潜在候选物之一。在这种情况下，出现了铅基陶瓷压电纳米发电机（PNG），它们有毒且容易疲劳破裂，对患者造成伤害。聚偏二氟乙烯-三氟乙烯（PVDF-TrFE）基薄膜也被开发为心脏能量采集器。在这里，我们展示了一个无电池心脏起搏器，该起搏器由生物相容性和柔性压电聚合物基纳米发电机（PNG）产生的电驱动，该发电器来自左心室的心脏运动。PNG由聚偏二氟乙烯（PVDF）的复合纳米纤维和由氧化锌（ZnO）和还原型氧化石墨烯（rGO）制成的杂化纳米填料组成。复合纳米纤维经过优化，可实现大功率输出。体内植入的优化PNG可以成功地从每个心跳中收获0.487μJ，这比人类心脏的起搏阈值能量大。自供电起搏器的成功演示使基于聚合物的PNG成为自供电生物医学植入物的可行候选产品之一。