High voltage generation from lead-free magnetoelectric coaxial nanotube arrays and their applications in nano energy harvesters

Abstract

Harvesting energy from surrounding vibrations and developing self-powered portable devices for wireless and mobile electronics have recently become popular. Here the authors demonstrate the synthesis of piezoelectric energy harvesters based on nanotube arrays by a wet chemical route, which requires no sophisticated instruments. The energy harvester gives an output voltage of 400 mV. Harvesting energy from a sinusoidal magnetic field is another interesting phenomenon for which the authors fabricated a magnetoelectric energy harvester based on piezoelectric-magnetostrictive coaxial nanotube arrays. Piezoelectric KNaNbO (KNN) is fabricated as the shell and magnetostrictive CoFeO (CFO) as the core of the composite coaxial nanotubes. The delivered voltages are as high as 300 mV at 500 Hz and at a weak ac magnetic field of 100 Oe. Further tailoring of the thickness of the piezoelectric and magnetic layers can enhance the output voltage by several orders. Easy, single-step wet chemical synthesis enhances the industrial upscaling potential of these nanotubes as energy harvesters. In view of the excellent properties reported here, the lead-free piezoelectric component (KNN) in this nanocomposite should be explored for eco-friendly piezoelectric as well as magnetoelectric power generators in nanoelectromechanical systems (NEMS).

Electromagnetic Properties of Cobalt Ferrite (CoFe2O4) with and without Addition of Niobium Pentoxide

“…There has been little research on niobium-doped spinel ferrites, apart from those such as Nb2O5-doped NiZn spinel ferrite [12], where it was observed that the addition of niobium considerably increased the grain size, as well as increasing the sintering temperature to 1250 °C in NiZn ferrite [12], and the formation of orthorhombic Nb2FeO6 was described as a secondary phase [13] with less than 1% niobia, or niobium-doped copper ferrite NbxCu1-xFe2O4, with x ≥ 0.1 [14]. Previous research on niobium-doped CoFe2O4 is scarce, with the exception of studies related to two-phase magnetoelectric ceramic composites with cobalt ferrite and ferroelectric niobates [15][16][17].…”

On nonlocal mechanics of curved elastic beams

“…A large number of contributions have been published on size-dependent structural behaviour of rods, wires, beams, membranes, plates and shells at micro-and nano-scales to conceive modern small-scale systems, such as: varactors (Sedighi et al, 2017), energy harvesters (Lekha et al, 2017), piezoelectric devices for biomedicine applications (Salim et al, 2018), resonators (Chorsi and Chorsi, 2018), resonant accelerometers (Ding et al, 2019), biosensors for detection of malaria protozoan parasites and of cancer , arch actuators (Ouakad and Sedighi, 2019). In this context, curved beams are the main structural elements of Micro/Nano-Electro-Mechanical-Systems (M/NEMS) resonators (Dantas and Gusso, 2018;Alfosail et al, 2019;Frangi and Gobat, 2019;Nikpourian et al, 2019;Ouakad and Najar, 2019;Sieberer et al, 2019;Wang and Ren, 2019) that should be designed by significantly taking small size effects into account.…”

Evaluation of vibration energy harvesting using a magnetostrictive iron–cobalt/nickel-clad plate

“…A promising methodology for resolving these problems is to harvest the dissipated energy (e.g. vibration) of the environment to form self-powered microsystems [4][5][6][7].…”