Hybrid chitosan-TiO2/ZnS prepared under mild conditions with visible-light driven photocatalytic activity.

Thin films of chitosan (CS) coated on glass substrates were used as support for the immobilization of nanostructures TiO2/ZnS via a mild chemical process followed by a hydrothermal treatment at 90 °C. The preparation route involved the coating of the CS film on the glass substrate followed by the deposition of a thin layer of Ti(OBu)4 precursor and immersion in a solution of Zn(O2CCH3)2 and Na2S. After a hydrothermal treatment at 90 °C, an even layer of TiO2 anatase decorated by ZnS nanorods was generated. Evidence of the formation of TiO2 anatase and ZnS was confirmed by XRD, Raman and XPS, and the morphology of the TiO2 layer and ZnS nanoparticles was analyzed by FE-SEM observations. The photocatalytic activity of the CS-TiO2-ZnS systems was evaluated by the degradation of a wide range of organic compounds including aromatic amines and carboxylic acids under a conventional halogen lamp.