Synthesis and Photocathodic Protection Properties of Nanostructured SnS/TiO₂Composites

Abstract

SnS/TiO2 nanocomposites were successfully fabricated by a successive ionic layer adsorption and reaction process. The effect of the material concentration on the preparation of the SnS/TiO2 composite films was discussed. TiO2 nanotube arrays co-sensitized with SnS nanoparticles were used as a photoanode to provide photoelectric protection for 304 stainless steel. The crystalline structures, morphology, and optical absorption property of the samples were measured by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The photo-generated cathodic protection performance was characterized by measuring the open-circuit potential and photocurrent density response, and by performing electrochemical impedance spectroscopy. The results indicate that the SnS/TiO2 composites have high light absorption and photo-electrochemical properties under visible light irradiation. The SnS/TiO2 composite prepared at the optimal concentration could shift the corrosion potential of the 304 stainless steel form −280 mV to −720 mV.