Giant enhancement in coercivity of ferromagnetic α-Fe2O3 nanosheet grown on MoS2

Abstract

To study the 2D materials, an interface interaction is very important to tune the physical properties because of the large specific surface area. When the antiferromagnetic α-Fe2O3 is grown in a single-crystalline form on a diamagnetic MoS2, enormous changes in magnetic properties are observed in the 2D composite system. Strong ferromagnetism with a giant coercivity of 1.8 T is observed in this single-crystalline α-Fe2O3/MoS2 heterostructure. It is noted that thinner sheets show better coercivity than the thicker sheets, and the coercivity decreases with the increase in temperature. This huge coercivity in larger and thinner single-crystalline α-Fe2O3 sheets grown on a MoS2 arises due to charge transfer from "S" to "Fe" and the surface pinning effect at the interface. A large negative magnetoresistance with a maximum value of 15% is achieved due to the spin-spin interaction, and a positive magnetoresistance is also observed at low field and high temperature as a result of the spin splitting effect.