This paper investigates the possibility of utilizing recycled PET bottle waste as matrix of novel composites. The effect of various MWCNT-ZnO quantum dot (QD) loadings (1, 2 and 4 by weight) on the morphology, thermal, electrical conductivity properties and water treatment of PET was studied. Results showed that the incorporation of MWCNT-ZnO QDs into the PET matrix causes that the pure polymer undergoes transition from electrically insulated to conductive at room temperature. Enhancement in thermal stability was obtained by the 4 wt% MWCNT-ZnO loading. Our results also show that rPET/MWCNT-ZnO QD composites can be used as absorbents for easy, convenient, and efficient removal of Cd(II) ions from aqueous solution. Actually, plastic waste was used and changed it to a valuable composite with potential of heavy metal adsorption as well as high electrical conductivity. (C) 2016 Elsevier B.V. All rights reserved.