Fig. 5: Demonstration of multiple battery-free IoT monitoring systems powered by Mn-doped PIN-PMN-PT generators.

a Schematic representation of multiple battery-free IoT monitoring systems. b Image of the experimental setup to operate multiple IoT sensors. c Voltage graph of the supercapacitor during the charging phase and operation of multiple IoT sensors powered by the MME harvester. d Screenshots of environmental monitoring displayed on smartphone applications for SimpleLink (i) and Thunderboard Sense 2 (ii) before and after sensing.