The shape dependence of magnetic and microwave properties for Ni nanoparticles

► Ni nanospheres and conical nanorods have been synthesized by facile wet chemical methods. ► Remanence ratio, coercivity, dynamic permeability and microwave absorbing properties show great dependence on particle shape. ► We simulate the complex permeability of Ni nanoparticles using random spatial distribution model of magnetic easy axes. ► Ni conical nanorods show good performances on microwave absorption.