Lead-free laminated structures for eco-friendly energy harvesters and magnetoelectric sensors

The ferromagnetic and ferroelectric laminated structure has been utilized to study the magnetoelectric (ME) effect, which holds great potential to fabricate micro-electro-mechanical devices with a high figure of merit. Designed a laminated heterostructure using ribbons of Metglas (Fe–Co–Si–B alloy) having high magnetic permeability and lead-free piezoelectric composites of 0.92(Na 0.5 Bi 0.5 )TiO 3 -0.08BaTiO 3 (NBT-BT) to generate the significant magnitude of direct ME voltage. The displacement-voltage measurements of NBT-BT yield a high response showing the nature of the piezoelectricity effect. The strength of ME coupling is determined from the ME voltage coefficient (α ME ), ME measurements have been carried out in the range of 0–6 kHz frequencies. The magnitude of the direct ME effect was found about 45–50 mV/Oe.cm over a low magnetic field of less than ±8 kOe. The real-time ME effect produced nearly 274.5 and 280.2 mV of ME voltages for the applied field of 200 and 300 Oe, respectively. It shows that the trilayer composite structure may be used as weak magnetic field sensors and energy harvesters. • The lead-free laminated structure of Metglas/NBT-BT/Metglas produces 45–50 mV/Oe.cm at a low magnetic field. • Real-time measurements of ME effect show ME voltages of 274.5 and 280.2 mV for the applied fields of 200 and 300 Oe, respectively. • The values of α E suggest that laminate structure has immense potential for ME-based low magnetic field sensor application.