The synthesis of polythionine (PTN)/cobalt-doped titanate nanotubes (CoTNTs) hybrid conducting films with distinct layouts, using electropolimerization, is reported. The CoTNTs nanocrystalline elongated particles were obtained by a hydrothermal treatment, using an amorphous Co-doped material as precursor. The adsorption ability of the prepared CoTNTs to remove organic dyes from aqueous media was investigated, using thionine (Th). The total amount of Th removed by the nanocrystalline CoTNTs powder was 340.06 mg g(-1). During this process, and due to the CoTNTs structural properties, the combination of dye adsorption and intercalation was considered. After dye sensitization, the Th/CoTNTs were characterized and used for Th electropolymerization studies, in order to produce hybrid polythionine (PTN) electroactive films. The electroactivity of the Th molecules after immobilization in the CoTNTs surface is maintained. After electropolymerization, stable and electroactive nanostructured CoTNTs-PTN modified electrodes were obtained. The influence of the experimental parameters in the final electrical and morphological properties of the obtained hybrid films was studied, mainly the presence of the monomer in solution, adsorbed or intercalated in CoTNTs. (C) 2013 Elsevier Ltd. All rights reserved.