J. Mater. Sci. Technol. ›› 2020, Vol. 37: 55-63.DOI: 10.1016/j.jmst.2019.07.034

• Research Article • Previous Articles     Next Articles

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

Xiayu Luab, Li Liuac*(), Xuan Xieac, Yu Cuia, Emeka E. Oguziecd, Fuhui Wangac   

  1. a Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
    b School of Materials Science and Engineering, University of Science and Technology of China, Shenyang, 110016, China
    c Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Materials Science and Engineering, Northeastern University, Shenyang, 110819, China
    d Electrochemistry and Materials Science Research Laboratory, Department of Chemistry, Federal University of Technology, P.M.B. 1526, Owerri, Nigeria
  • Received:2019-05-14 Revised:2019-06-26 Accepted:2019-07-08 Published:2020-01-15 Online:2020-02-10
  • Contact: Liu Li

Abstract:

A 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-vis 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.

Key words: TiO2 nanotubes, Graphene, Co(OH)2 nanoparticles, Photoelectrochemical performance, Photogenerated cathodic protection