Synthesis of Ferromagnetic Nd2Fe14B Nanocrystalline via Solvothermal Decomposition and Reduction–Diffusion Calcination

Monodispersed and highly crystalline Nd₂Fe₁₄B ferromagnetic nanoparticles were chemically synthesized by two steps. Uniform NdFeBO nanoparticles (~100 nm) were obtained via solvothermal decomposition in the presence of oleic acid, oleylamine, and hexadecyl trimethyl ammonium bromide. Prior to thermal treatment, thin CaO layer was covered onto oxide nanoparticles to maintain Nd/Fe ratio (1/8) at high temperature. After thermal diffusion-reduction annealing at 800 °C, Nd₂Fe₁₄B nanocrystalline of small particle size (~ 80 nm) revealed observable coercivity (400 Oe).