Ferrofluid Mn_0.5Zn_0.5Fe₂O₄ as Harvesting Energy: Preliminary Study

Abstract

Currently humans are still very dependent on resources derived from fossil fuels. Even though fossil fuels are no longer sufficient to meet energy needs. For this reason, renewable energy technology is developed in the form of energy harvesting from mechanical energy in the form of ferrofluid vibrations. The ferrofluid used in this study is composed of filler Mn0.5Zn0.5Fe2O4 where Zn doping is used to increase magnetization, surfactant tetramethylammonium hydroxide (TMAH), and H2O as a liquid carrier. This study aims to study ferrofluid Mn0.5Zn0.5Fe2O4 as energy harvesting. Mn0.5Zn0.5Fe2O4 nanoparticles were synthesized using the coprecipitation method accompanied by nanostructure studies in the form of XRD, FTIR and VSM tests to determine the diffraction peaks, functional groups and magnetic properties of the sample. The diffraction peaks of Mn0.5Zn0.5Fe2O4 are at the peaks (2 2 0), (3 1 1), (2 2 2), (4 0 0), (4 2 2), (5 1 1), and (4 4 0). The FTIR spectrum of Mn0.5Zn0.5Fe2O4 nanoparticles is shown in the wavelength range of 4000-500 cm−1. The band vibration peaks of O-H stretching, CO2, O-H, Mn-O, Zn-O, and Fe-O particles Mn0.5Zn0.5Fe2O4 are respectively at 3392 cm−1, 2309 and 2376 cm−1, 1635 cm−1, 861 and 1636 cm−1, 686 cm−1 and 539 cm−1. The functional group of the metal-oxygen group (M–O) originates from magnetic particles as fillers to form ferrofluids. The competition of Mn and Zn ions at octahedral and tetrahedral sites in the spinel system tends to change the lattice parameters of the Mn0.5Zn0.5Fe2O4 ferrofluid. The magnetization curve of the Mn0.5Zn0.5Fe2O4 ferrofluid has superparamagnetic characteristics with a saturation magnetization value of 31,727 emu/g so it can be used as an energy harvester. Based on the IV electrical test, the Mn0.5Zn0.5Fe2O4 ferrofluid has the potential for energy harvesting with a voltage value of 1.67 µV and a current of 136.6 µA.