Study on the physicochemical properties of poly(methylmethacrylate) (PMMA) modified Pd/Fe nanocomposites: Roles of PMMA and PMMA/ethanol

To probe the roles of poly(methylmethacrylate) (PMMA) and PMMA/ethanol in controlling the physicochemical properties of Pd/Fe nanoparticles (NPs) and explore a feasible approach to fabricating highly reactive Pd/Fe NPs, we modified Pd/Fe NPs with PMMA and PMMA/ethanol via aqueous chemical reduction. The particle dispersion and resisting oxidation ability were enhanced by modification with PMMA and PMMA/ethanol, and the 2,4-dichlorophenol dechlorination efficiency increased with the increased molar ratio of PMMA to iron and ethanol to iron. During the preparation, the roles of PMMA and PMMA/ethanol were to control particle agglomeration and oxidation, while those for the dechlorination process were to offer more reactive surfaces and access of active reaction sites to contaminants. Compared to the unmodified process, the modification process resulted in a different dechlorination process mainly resulted from the roles of PMMA and PMMA/ethanol in regulating properties of Pd/Fe NPs. In addition, the roles of PMMA and PMMA/ethanol in 2,4-dichlorophenol dechlorination kinetics using Pd/Fe NPs were revealed. The ethanol introduced enhanced the particle resisting oxidation ability and prolonged its longevity. These results demonstrated that the PMMA and ethanol had played a favorable role in promoting colloidal stability and improving dechlorination ability of Pd/Fe NPs.