Rollable Magnetoelectric Energy Harvester as Wireless IoT Sensor.

Perhaps the most abundant form of waste energy in our surrounding is the parasitic magnetic noise arising from electrical power transmission system. In this work, a flexible and rollable magneto-mechano-electric nanogenerator (MMENG) based wireless IoT sensor has been demonstrated in order to capture and utilize the magnetic noise. Free standing magnetoelectric (ME) composites are fabricated by combining magnetostrictive nickel ferrite nanoparticles and piezoelectric polyvinylidene-co-trifluoroethylene polymer. The magnetoelectric 0-3 type nanocomposites possess maximum ME co-efficient of 11.43 mV/cm-Oe. Even, without magnetic bias field 99 % of the maximum ME co-efficient value is observed due to self-bias effect. As a result, the MMENG generates sufficient peak-to-peak open circuit voltage, output power density and successfully operates commercial capacitor under the weak and low frequency stray magnetic field arising from the power cable of home appliances such as, electric kettle. Finally, the harvested electrical signal has been wirelessly transmitted to a smart phone in order to demonstrate the possibility of position monitoring system construction. This cost effective and easy to integrate approach with tailored size and shape of device configuration is expected to be explored in next-generation self-powered IoT sensors including implantable biomedical devices and human health monitoring sensory systems.