The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure o...The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure of the cobalt NCs were determined by XRD. The results showed that each of the cobalt nanoparticles is a single crystal with a complex cubic structure relating to the β phase of manganese. The XPS spectra indicate that the surface of Co nanoparticles was not oxidized or formed other compound. Two-dimensional order superlattices of the Co nanoparticles were formed by self-assembly technique.展开更多
采用高温有机液相法,以醋酸镍为前驱体,用三辛基膦作表面活性剂,用连续注入的方式,在不同的反应阶段加入三辛基膦,制备了Ni_3C@Ni核壳型纳米粒子(NPs)。催化性能研究表明,该核壳结构的活化能ΔE=60 k J/mol,低于单一镍纳米粒子(ΔENi=65...采用高温有机液相法,以醋酸镍为前驱体,用三辛基膦作表面活性剂,用连续注入的方式,在不同的反应阶段加入三辛基膦,制备了Ni_3C@Ni核壳型纳米粒子(NPs)。催化性能研究表明,该核壳结构的活化能ΔE=60 k J/mol,低于单一镍纳米粒子(ΔENi=65 k J/mol)的活化能;磁学性能研究表明,该纳米粒子为铁磁性,在300 K时的矫顽力为65.2 Oe,饱和磁感应强度为0.25 emu/g。退火后的产物为镍/氧化镍的核壳结构。电化学性能研究表明,该核壳结构具有较为稳定的循环可逆性,首次充放电容量较高,可作为新型锂离子电池负极材料。展开更多
文摘The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure of the cobalt NCs were determined by XRD. The results showed that each of the cobalt nanoparticles is a single crystal with a complex cubic structure relating to the β phase of manganese. The XPS spectra indicate that the surface of Co nanoparticles was not oxidized or formed other compound. Two-dimensional order superlattices of the Co nanoparticles were formed by self-assembly technique.
文摘采用高温有机液相法,以醋酸镍为前驱体,用三辛基膦作表面活性剂,用连续注入的方式,在不同的反应阶段加入三辛基膦,制备了Ni_3C@Ni核壳型纳米粒子(NPs)。催化性能研究表明,该核壳结构的活化能ΔE=60 k J/mol,低于单一镍纳米粒子(ΔENi=65 k J/mol)的活化能;磁学性能研究表明,该纳米粒子为铁磁性,在300 K时的矫顽力为65.2 Oe,饱和磁感应强度为0.25 emu/g。退火后的产物为镍/氧化镍的核壳结构。电化学性能研究表明,该核壳结构具有较为稳定的循环可逆性,首次充放电容量较高,可作为新型锂离子电池负极材料。