Harvesting Magneto-Acoustic Waves Using Magnetic 2D Chromium Telluride (CrTe3)

Small. 2024. Vol. 20. No. 47. Article 2405197.

Chowde Gowda C., Alexey Kartsev, Tiwari N., Sarkar S., Safronov A., Chaudhary V., Sekhar Tiwary C.

A vast majority of electrical devices have integrated magnetic units, which generate constant magnetic fields with noticeable vibrations. The majority of existing nanogenerators acquire energy through friction/mechanical forces and most of these instances overlook acoustic vibrations and magnetic fields. Magnetic two-dimensional (2D) tellurides present a wide range of possibilities for devising a potential flexible energy harvester. 2D chromium telluride (2D CrTe3) is synthesized, which exhibits ferromagnetic behavior with a higher T c of ≈224 K. The structure exhibits stable high remnant magnetization, making 2D CrTe3 a potential material for harvesting magneto-acoustic waves. A magneto-acoustic nanogenerator (MANG) is fabricated and the basic mechanical stability and sensitivity of the device with change in load conditions are tested. A high surface charge density of 2.919 mC m−2 is obtained for the device. The thermal strain created in the lattice structure is examined using in-situ Raman spectroscopy. The magnetic anisotropy energy (MAE) responsible for long-range FM ordering is calculated by theoretical modelling with insights into opening of electronic bandgap which enhances the flexoelectric effects. The MANG can be a potential NG to synergistically tap into the magneto—acoustic vibrations generated from the frequency changes of a vibrating device such as loudspeakers.

Keywords: magnetoacoustic waves, 2D materials, DFT ab initio calculations, ultrathin magnets