The　sidewalls　of　multiwalled　carbon　nanotubes　(MWCNTs)　were　decorated　with　CdS　nanoparticles　using　a　mild　two-step　approach,　with　in　situ　polymerized　thiophene　(PTh)　acting　as　an　interlinker.　Extensive　characterization　of　the　materials　has　been　carried　out　using　transmission　electron　microscopy,　selected　area　electron　diffraction,　X-ray　diffraction,　thermal　gravimetric　analysis,　ultraviolet-visible　absorption　spectroscopy　and　photoluminescence　spectroscopy.　optical　limiting　(OL)　studies　have　been　performed　using　the　open　Z-scan　technique　at　the　laser　wavelengths　of　532　and　1064　nm.　The　MWCNT-PTh-CdS　system　shows　an　enhanced　OL　effect　in　comparison　to　the　pristine　MWCNTs,　particularly　at　1064　nm.　Possible　underlying　mechanisms　are　proposed　based　on　the　results　of　nonlinear　scattering　measurements.　(C)　2009　Elsevier　Ltd.　All　rights　reserved.