Fabrication of SrTiO3 Nanocrystalline Film Photoelectrode and Its Photoelectrochemical Anticorrosion Properties for Stainless Steel

The photoelectrochemical properties of a SrTiO3 film coated on an indium-tin oxide (ITO) conducting glass were investigated for the anticorrosion of 304 stainless steel (304SS) under solar light illumination. The SrTiO3 nanocrystal powders were synthesized using a sol-gel process in the absence and presence of the cetyltrimethyl ammonium bromide (CTAB) surfactant and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was showed that the as-synthesized SrTiO3 materials exhibit a single perovskite structure and the presence of CTAB leads to uniform particles with an average size of 90 nm. The UV-Vis diffuse reflectance analysis shows that both SrTiO3 films that were prepared in the absence and presence of CTAB surfactant absorbs strongly in the UV region with an absorption threshold edge near 380 nm while the SiTiO3 prepared in the presence of CTAB exhibited a stronger absorption in the UV region than those in the absence of CTAB. The photo-electrochemical anticorrosion effects of SrTiO3 on 304 stainless steel substrates in a 0.5 mol.L-1 NaCl solution were investigated using a 0.1 mol.L-1 NaOH and 0.2 mol.L-1 Na2S hole sacrifice electrolyte solution. Metallographic images of the 304 stainless steel before and after immersion in a 0.5 mol.L-1 NaCl+0.05 mol.L-1 HCl solution for 6 h demonstrates that the SrTiO3 film coated photoelectrode exhibits excellent photoelectrochemical anticorrosion performance on 304 stainless steel.