Improved Coercivity of Solvothermally Grown Hematite (alpha-Fe2O3) and Hematite/Graphene Oxide Nanocomposites (alpha-Fe2O3/GO) at Low Temperature

alpha-Fe2O3 and alpha-Fe2O3/graphene oxide (GO) nanocomposites are synthesized by solvothermal method in acetonitrile medium at 200 degrees C. XRD studies reveals the formation of alpha-Fe2O3 and alpha-Fe2O3/GO nanocomposites. Raman studies indicate that GO in alpha-Fe2O3/GO system was more disordered than GO. The enhanced low temperature magnetic saturation and coercivity in alpha-Fe2O3 and alpha-Fe2O3/GO are related to frozen canted spins. Blocking temperature of alpha-Fe2O3/GO is 348 K, which also shows higher coercivity of the order of about 3064 Oe at 5 K. The alpha-Fe2O3/GO composite exhibits thermal hysteresis at Morin transition (Delta T-M = 11K)