The effect of activation pretreatment on the morphology of Ag microsphere and the microwave absorption performances of Ag@MWCNTs hybrids

Abstract The silver microspheres with controllable morphology and structure were prepared by electroless plating with activated PS microspheres as template, which were used to construct a 3D absorbing hybrids of Ag@MWCNTs. The SEM and EDS results illustrated that a uniform silver shell was coated on the surface of PS microsphere because of the activation, which was conductive to construct an excellent conductive network to attenuate electromagnetic wave. Meanwhile, the plating solution concentration had an important effect on the morphology of Ag microsphere and microwave absorption performances of the absorbing hybrids. When the concentration was 12 g/L, the silver shell of B-2 microsphere was uniform and dense. However, lower or higher concentration were unfavorable to the integrity of Ag shell of B-1 and B-3 microsphere. For the B-2@MWCNTs absorbent hybrids, the reflection loss value was −37.00 dB at 9.9 GHz, while that of B-1@MWCNTs and B-3@MWCNTs hybrids were −27.35 dB at 8.5 GHz and −24.07 dB at 11.3 GHz, respectively. All the results indicated that the controlling measures of activation for PS microspheres and proper plating solution concentration are crucial to enhance the microwave absorbing performances of absorbing hybrids.