Template-free synthesis of Ni microfibres and their electromagnetic wave absorbing properties

A template-free procedure for preparing Ni microfibres was reported, by which Ni microfibres with diameters of 0.5-1.0 mu m and aspect ratios of 20-30 were successfully prepared. A proposed crystallites aggregation formation mechanism was discussed to explain the formation of the Ni microfibres. The relative complex permittivity and permeability of paraffin/50 wt% Ni microfibres composite were measured in a frequency range of 2-18 GHz. The minimum reflection loss of -21.3 dB was obtained at 14.7 GHz with a composite thickness of 2.0 mm, and the bandwidth corresponding to reflection losses below -10 dB is 5.9 GHz.