All-inorganic flexible piezoelectric energy harvester enabled by two-dimensional mica

A flexible piezoelectric material with a high mechanical-to-electrical energy conversion performance is a promising strategy for battery-less microrobotics, autonomous sensors networks and wearable/implantable biomedical devices. However, a cost-effective, simple preparation technology for all-inorganic flexible piezoelectric perovskite materials have not developed prior to this study for mechanical energy harvesting applications. In this communication, for the first time, we report a cost-effective, one-step process to fabricate large-scale, light-weight and all-inorganic PbZr0.52Ti0.48O3 (PZT) flexible piezoelectric energy harvesters, based on unique two-dimensional mica substrates via a sol-gel method. The maximum output current, voltage and power density of flexible PZT nanogenerators reached to ~ 0.28 μA, 120 V and 42.7 mW cm−3, respectively. Furthermore, the flexible PZT nanogenerators based on this “one-step” process could be continuously bended and unbended at a high strain for 40,000 times without obvious decline of output voltage, showing an excellent mechanical and electrical durability.219