Fabrication of flower-like Ni0.5Co0.5(OH)2@PANI and its enhanced microwave absorption performances

Ni0.5Co0.5(OH)(2) with flower-like structure@PANI was designed and synthesized via a two-step route. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) results illustrated that the Ni0.5Co0.5(OH)(2) had a 3D flower structure with a homogeneous distribution. The Ni0.5Co0.5(OH)(2) was coated by polyaniline (PANI) and embedded in polyaniline matrix. The as-synthesized Ni0.5Co0.5(OH)(2)@PANI possessed a BET specific surface area of 58.82 m(2) g(-1), and its pore diameter was in the mesoporous range (3.93 nm). Investigations of EM wave absorption properties indicated that the maximum absorption intensity of Ni0.5Co0.5(OH)(2)@PANI was as high as -39.8 dB at 6.4 GHz and the absorption bandwidth exceeding -10 dB was 3.1 GHz (4.9-8 GHz) with a matching thickness of 2.5 mm. The excellent EM wave absorption properties of the material were ascribed to its high permittivity and improved impedance matching effect. Therefore, it is anticipated that the Ni0.5Co0.5(OH)(2)@PANI composite would serve as a promising microwave absorber.