Synthesis of Ni Nanochains with Various Sizes: The Magnetic and Catalytic Properties

A series of pure Ni thin chains with particle diameters ranging from 15 to 80 nm were successfully synthesized by a wet chemical method. Magnetization measurements for the Ni chains reveal that the saturation magnetization increases and the coercivity decreases with increasing particle diameter. The magnetization reversal mechanism of both the samples with a diameter of 30 and 50 nm can be described by the model of “chain of spheres”. Using the fanning mode, the calculated coercivities and the remnant ratios agree well with the experimental results. Surprisingly, the coercivity is greatly enhanced, reaching as high as 790 Oe at T = 5 K for the Ni chains with a diameter of ∼15 nm, which are composed of single-crystal particles. Meanwhile, in the degradation of pentachlorophenol (PCP) solutions with Fe 0 nanoparticles as reducing agents, Ni nanochains with a diameter of ∼80 nm were added, and the results indicate that the sample could serve as a good catalyst in dechlorination systems.