The core-shell Ni(OH)(2)@Mg(OH)(2) (NM) hybrids were synthesized via precipitation of Ni(OH)(2) on the surface of Mg(OH)(2) (MH) nanoplates at room temperature. It was demonstrated that PP/NM displayed outstanding smoke suppression in comparison with PP/MH owing to the catalytic chaffing of PP/NM for generating vast multiwalled carbon nanotubes (MWCNTs), which facilitated the formation of compact char layers. Based on this study, the novel NM hybrids as catalytic flame retardants possessed the potential to eliminate the smoke hazard of the polyolefins system.