Self-powered energy-harvesting magnetic field sensor

Driven largely by the recent growth in the Internet of Things, there is a rapid surge in the demand for low-powered or self-powered sensors and devices. Here, we report a fully self-powered magnetic sensor system based on the magnetoelectric (ME) effect. This device consists of both a field-detection element and a power-generation element, which are designed using magnetostrictive Metglas amorphous ribbons and piezoelectric PMN-PT single crystal plates, respectively. The ME laminates for energy harvesting exhibit a giant resonance magnetic responsivity of 350 nC/Oe at 15 kHz. The magnetic-field sensing element shows a linear response with a high resolution up to 32 nT, and the magnetic-harvest element can reach a power of 48.68 mW/Oe at an optimum load resistance of 5 kΩ. The self-powered sensor system has shown excellent capability to convert magnetic energy into electrical energy, as demonstrated in powering a small electronic screen. The high sensitivity and power generation of our system suggest potential applications in sustainable intelligent sensor networks.