HPHT synthesis and magnetic property of -Fe2O3@C core-shell nanorods

-Fe2O3@C core-shell nanorods with average diameter of 20 nm and length of 150 nm are synthesized by transforming FeOOH@PVA nanorods under the condition of high pressure and high temperature (HPHT). The FeOOH@PVA nanorods are prepared via a hydrothermal route. The best synthesis condition for transforming FeOOH@PVA core-shell nanorods into -Fe2O3@C nanorods is 400 ℃ under 1 GPa. Owing to high aspect ratios, the -Fe2O3@C nanorods present a high coercivity of 330 Oe (10 Oe=79.5775 A/m). The possible mechanism for the synthesis of -Fe2O3@C nanorods is also discussed. The HTHP method can provide a new way for preparing of one-dimensional core-shell nanostructures.