Preparation and Magnetic Properties of La-Co Co-Doped M-Type Strontium Ferrite Nanofibres

Abstract

Polyethylene pyrrole(PVP)and metal nitrate were used as precursors,La and Co co-doped M-type strontium ferrites Sr 1-x La x Fe 12-x Co x O 19 (x=0.12)(SLFC)were prepared by electrospinning,sol-gel, and subsequent heat treatment processing.The crystal structure,morphology,and magnetic properties of the samples were studied by means of X-ray diffraction(XRD),scanning electron microscopy(SEM), transmission electron microscopy(TEM),and superconducting quantum interference device(SQUID).The influences of the variation of sintering temperature on the magnetic properties of SLFC were systematically investigated.The experimental results show that the optimum values of the magnetic properties were obtained at 950°C for 2 h,and the coercivity(H c ),saturation magnetization(M s ),and remanence(M r )values of the samples were 498.53 kA·m -1 ,70.76 A·m 2 ·kg -1 ,and 36.35 A·m 2 ·kg -1 , respectively.Pure-phase bamboo-like SLFC nanofibres with diameter of about 55 nm were fabricated. The magnetic properties of undoped SrFe 12 O 19 (SF)were improved obviously,and the SF nanofibres exhibited better magnetic properties than the corresponding nanoparticles obtained by the sol-gel processing.