A flexible magnetic field sensor based on paramagnetic C60@Fe3O4 nanocomposites and ordered hexagonally structured substrate

Abstract

Magnetic field detection is one of the most important processes in academic and industrial applications. Flexible magnetic field sensors are often fabricated with magnetic nanoparticles. Superparamagnetic materials have better repeatability than ferromagnetic materials, but the sensitivity needs to be further improved. To solve this problem, in this paper we used C60@Fe3O4 which is superparamagnetic and has good dispersion as a sensitive material, and ordered hexagonally structured substrate was fabricated by light curing 3D printing technology to enhance the magnetic response of the sensor. Then we compared the magnetic response characteristics of three different size magnetic field sensors. We found that the medium size sensor has better sensitivity and the maximum sensitivity of magnetic field in the range of 0–400 mT is 0.097 T-1. In order to further explore the mechanism of the sensor, we used digital microscope to observe the changes of the sensor surface under the magnetic field, and further put forward the microstructure evolution model of the conductive network under the magnetic field. The sensor described in this paper can be used for repetitive magnetic field sensing without remanence.