(1. 江蘇科技大學(xué) 數(shù)理學(xué)院，鎮(zhèn)江 212003；
2. 江蘇大學(xué) 材料科學(xué)與工程學(xué)院，鎮(zhèn)江 212013)
摘 要: 采用溶膠-凝膠結(jié)合靜電仿絲技術(shù)制備Co0.5Ni0.5Fe2O4納米纖維，然后將其氫熱還原合成了一系列不同合金含量、平均直徑在67~85 nm的Fe-Co-Ni合金/Co0.5Ni0.5Fe2O4復(fù)合納米纖維。采用TG-DTA、XRD、FE-SEM、TEM和VSM對所得纖維樣品進(jìn)行表征。結(jié)果表明：隨著還原溫度由290 ℃升高到350 ℃，纖維直徑逐漸減小，微觀形貌向串珠狀結(jié)構(gòu)演變，還原產(chǎn)物中Fe-Co-Ni合金的質(zhì)量分?jǐn)?shù)由15.2%逐步增加到約95.7%；所制得的Fe-Co-Ni合金/Co0.5Ni0.5Fe2O4復(fù)合納米纖維的兩磁性相晶粒間具有良好的磁交換耦合，其磁化行為如同單相磁性材料的；隨Fe-Co-Ni合金含量的增加，其飽和磁化強(qiáng)度和剩磁均增大，而相應(yīng)的矯頑力則呈現(xiàn)出一個先增大后減小的變化趨勢；Fe-Co-Ni合金相的形成不僅能夠明顯提高復(fù)合納米纖維的軟磁性能，而且通過調(diào)節(jié)其含量還可有效實(shí)現(xiàn)對材料磁參數(shù)的寬范圍調(diào)控。
關(guān)鍵字: Co-Ni鐵氧體；Fe-Co-Ni合金；復(fù)合納米纖維；磁性能；靜電紡絲；氫熱還原
（1. School of Mathematics and Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China;
2. School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China）
Abstract:A series of Fe-Co-Ni alloy/Co0.5Ni0.5Fe2O4 composite nanofibers with average diameters from 67 to 85 nm and various alloy contents were synthesized by hydrogen-thermal reduction of Co0.5Ni0.5Fe2O4 nanofibers prepared via sol-gel methode and electrospinning. The obtained nanofiber samples were characterized by TG-DTA, XRD, FE-SEM, TEM and VSM. The results show that the mass fraction of Fe-Co-Ni alloys in the reduced products progressively increases from 15.2% to about 95.7% with increasing the reduction temperature of Co0.5Ni0.5Fe2O4 nanofibers from 290 ℃ to 350 ℃. Meanwhile, the fiber diameter gradually decreases and the fiber surface morphology evolves toward the bead-like structures. The magnetic field dependence of the magnetization behaves as if the as-prepared Fe-Co-Ni alloy/Co0.5Ni0.5Fe2O4 composite nanofibers are single-phase magnetic materials, which indicates that the two magnetic phases in composites are effectively exchange-coupled and that the magnetization of both phases reverses cooperatively. The saturation magnetization and remanence of the samples increase monotonically with the increase of Fe-Co-Ni alloy content, while the corresponding coercivity shows a trend of first increase and then decrease. The formation of Fe-Co-Ni alloy phase can not only obviously improve the soft magnetic performance of the composite nanofibers, but also effectively realize the wide-range control for the magnetic parameters through adjusting the Fe-Co-Ni alloy content in composites.
Key words: Co-Ni ferrite; Fe-Co-Ni alloys; composite nanofiber; magnetic property; electrospinning; hydrogen-thermal reduction
