磁性纳米粒子SmCo_5的合成及表征

Synthesis and Characterization of Magnetic Nanoparticles SmCo_5

SmCo5纳米粒子是重要的双金属稀土磁性材料。用四步制备了SmCo5纳米粒子。调节SmCl3和CoCl2混合溶液的pH至合适值后,加热回流,使得Sm3+和Co2+水解共沉淀。150℃下水热反应,制得粒径约为20nm的立方钐钴氧化物纳米粒子。最后,将水热制备的纳米氧化物在400℃氢气流中,以金属钠为还原剂,制得SmCo5纳米粒子。300K纳米粒子呈超顺磁状态,而5K时粒子呈铁磁状态,矫顽力为4.16×104A/m。

SmCo5 nanoparticles are one of the most important binary transition metal-rare earth systems for magnetic materials. SmCo5 nanoparticles were fabricated by a four-stage route. At first, pH value of mixed aqueous soluble with SmCl3 and CoCl2 was adjusted using NaOH. Secondly, two soluble metal-salts were forced hydrolysis to oxides under atmospheric refluxing at 80 ℃. Then, oxide nanoparticles with a ca average size of 20 nm were prepared at 150 ℃ for 9 h through a convenient hydrothermal process. Finally, the SmCo5 nanoparticles were attained via hydrothermally prepared nanoparticles deoxidized using Na under the hydrogen stream at 400 ℃. The SmCo5 nanoparticles are superparamagnetic at 300 K while the particles are ferromagnetic with H c of 4.16×10 4 A/m at 5 K.