Magnetite Nanofluids from Natural Sand for Temperature Sensor Application: A Preliminary Study

Abstract

In this study, magnetite nanofluids have been developed from natural sand for temperature  sensor application. On the basis of the results of XRD data analysis, it was known that the  nanoparticles as fillers of the nanofluids had a single phase, namely magnetite with an  inverse cubic spinel structure with a crystallite size of 11 nm. The SEM image showed that  the nanoparticles were composed of spherical particles and tended to agglomerate with a  particle size distribution of 38 nm. The octahedral and tetrahedral Fe-O functional groups  were detected at wavenumbers of 506 cm-1 and 762 cm-1 which confirmed the presence of  magnetite. The band gap energy value of the magnetite nanoparticles was 2.797 eV. Furthermore, the temperature sensor test showed that the output laser intensity of the  magnetite nanofluids increased with increasing temperature. The best dilution with the  volume composition of H2O:nanofluids (1:4) achieved the best sensitivity for temperature  sensor application.