BACKGROUNDIn this work, novel multisensitive composites of poly(N-isopropylacrylamide-co-acrylic acid-co-cobalt tetra(N-carbonylacrylic) aminophthalocyanine))/TiO2 (poly(NIPAM-co-AAc-co-CoMPc)/TiO2) were prepared to address the problems of low efficiency for utilizing solar light and difficult separation and recovery of nanometer sized TiO2 particles in the photocatalytic degradation of dinitro butyl phenol (DNBP) in wastewater. RESULTSThe results showed that nanometer sized TiO2 particles were successfully encapsulated in multisensitive polymer carriers of spherical shape and that the composite photocatalyst can be activated by both ultraviolet and visible light. The synthesized composites exhibited high sensitivity to external temperature and pH stimuli. The satisfactory removal of DNBP from aqueous solution can be achieved at pH 5.62 with catalyst concentration of 6 g L-1 under visible light irradiation for 5 h. The multisensitive composites prepared in this study have repeatability. CONCLUSIONThe synthesized multisensitive composites can be used to perform on-off' photocatalytic degradation of organic contaminants in water under visible light irradiation by controlling temperature or pH. (c) 2013 Society of Chemical Industry