A highly efficient In₂S₃/Ag₂S/TiO₂ NTAs photoelectrodes for photocathodic protection of Q235 carbon steel under visible light

Abstract

A novel In2S3/Ag2S/TiO2 nanotube arrays (NTAs) was successfully fabricated by successive ionic layer adsorption and reaction (SILAR) method and electrochemical anodic oxidation method, and served as photoanode for photocathodic protection application. The micromorphologies, optical absorption properties, crystalline structure and elemental valence states of the composites were performed by field emission scanning electron microscopy, high resolution transmission electron microscope, UV−vis diffuse reflectance absorption spectra, X-ray diffractometer and X-ray photoelectron spectroscopy, respectively. The photocathodic protection performances of In2S3/Ag2S/TiO2 NTAs on the Q235 carbon steel (CS) were also studied. The In2S3/Ag2S/TiO2 nanocomposites show better photoelectrocatalytic and photocathodic protection performance than pure TiO2 NTAs. The photocurrent density of In2S3(9)/Ag2S(8)/TiO2 photoelectrode coupled with Q235 CS reach 211 μA cm−2, which is about 4.5 times higher than that of TiO2 NTAs. The photogenerated potential of Q235 CS coupled to In2S3(9)/Ag2S(8)/TiO2 under illumination shows a negative shift to −0.92 V vs. SCE. Results indicate that the co-sensitization of In2S3 and Ag2S could extend the light absorption of TiO2 to the visible light range and enhance its photoelectric conversion efficiency.microscope, UV−vis diffuse reflectance absorption spectra, X-ray diffractometer and X-ray photoelectron spectroscopy, respectively. The photocathodic protection performances of In2S3/Ag2S/TiO2 NTAs on the Q235 carbon steel (CS) were also studied. The In2S3/Ag2S/TiO2 nanocomposites show better photoelectrocatalytic and photocathodic protection performance than pure TiO2 NTAs. The photocurrent density of In2S3(9)/Ag2S(8)/TiO2 photoelectrode coupled with Q235 CS reach 211 μA cm−2, which is about 4.5 times higher than that of TiO2 NTAs. The photogenerated potential of Q235 CS coupled to In2S3(9)/Ag2S(8)/TiO2 under illumination shows a negative shift to −0.92 V vs. SCE. Results indicate that the co-sensitization of In2S3 and Ag2S could extend the light absorption of TiO2 to the visible light range and enhance its photoelectric conversion efficiency.

Fabrication of Z-Scheme TiO2/Au/CdS Nanostructured Coating with Enhanced Photocathodic Protection Performance for Carbon Steel

“…The photogenerated electrons in g-C 3 N 4 migrate unidirectionally to the protected metal, thus preventing the corrosion of the matrix. Li et al prepared a ternary In 2 S 3 /Ag 2 S/TiO 2 system. In 2 S 3 and Ag 2 S enhance the absorption of visible light, so the nanocomposites are coupled with carbon steel and the photocurrent density reaches 211 μA·cm –2 , which is about 4.5 times higher than that of TiO 2 .…”

Review of TiO2-Based Heterojunction Coatings in Photocathodic Protection

“…When increasing deposition cycles, irregular aggregation of SnS 2 is produced on the surface of the TiO 2 coating. Li et al 91 prepared In 2 S 3 /Ag 2 S/TiO 2 heterojunction coatings utilizing the two-step SILAR method. The XRD results indicated that the prepared coating has a high purity.…”

Review on the Solar-Driven Photocathodic Protection of Metals in the Marine Environment

“…Under white light illumination, the composite film photoanode lowered the potential of coupled 403 SS in a 0.5 M NaCl solution by 680 mV, showcasing a markedly enhanced effect of photo-electro-chemical cathodic protection. Li et al [27] successfully prepared a novel In 2 S 3 /Ag 2 S/TiO 2 nanotube array using continuous ion layer adsorption and electrochemical anodic oxidation methods and applied it as a photoanode for photo-electro-chemical cathodic protection. The study showed that compared to pure TiO 2 , the In 2 S 3 /Ag 2 S/TiO 2 nanocomposite exhibited better photoelectrocatalytic and photo-electro-chemical cathodic protection performance.…”