Synergetic effect of graphene and Co(OH)2 as cocatalysts of TiO2 nanotubes for enhanced photogenerated cathodic protection

Publication date: Available online 5 September 2019Source: Journal of Materials Science & TechnologyAuthor(s): Xiayu Lu, Li Liu, Xuan Xie, Yu Cui, Emeka E. Oguzie, Fuhui WangAbstractA layer of graphene (GR) particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes, aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor TiO2. The obtained Co(OH)2/GR/TiO2 was extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible absorption spectra and photoluminescence (PL) emission spectra. Electrochemical impedance spectra, photogenerated potential-time (E-t), photocurrent density-time (i-t) and i-E curves and open circuit potential (OCP) curves were measured to investigate the photoelectrochemical activities and photogenerated cathodic protection properties. The results revealed that Co(OH)2/GR/TiO2 exhibits excellent photoelectrochemical and photogenerated cathodic performance due to synergistic effect between Co(OH)2 and graphene. Co(OH)2 and graphene co-modified TiO2 photoanode could provide an effective protection for 304 stainless steel (304SS) in 3.5 wt% NaCl solution for 12 h, which would be promising for future practical applications in the field of marine corrosion protection.
Source: Journal of Materials Science and Technology - Category: Materials Science Source Type: research