Boosted photoelectric cathodic protection exerted by 3D TiO/AgInS/InS nanomultijunction for pure copper in NaCl solution

The global annual consumption of marine metal corrosion is a significant challenge to the service life of metals and the development of marine strategies. A tri-dimensional AgInS/InS co-modified TiO nanobush (NB) superstructure photoanode is constructed. It shows superior photoelectric cathodic protection (PECP) characteristic for pure copper whose self-corrosion potential is more negative in simulated natural marine environment without additional any hole scavengers under simulated solar light illumination. Origin from the more negative energy level potential of AgInS/InS, the quasi-Fermi level of the photogenerated electrons of TiO NB/AgInS/InS was pull to a more negative position, reinforcing the transmission of photogenerated electrons to the pure copper whose self-corrosion potential is more negative. The sensitizer AgInS together with the assistant layer InS dramatically enhances the PECP performance of TiO NB/AgInS/InS. The tri-dimensional ultrafine branch-like architecture of TiO NB with the nanoparticles quickens the collection and transfer of photogenerated electrons to the metallic pure copper. This environmentally friendly 3D photoanode structure provides a good reference for the optimized construction of photoelectric materials for marine metal corrosion protection. Graphical abstract: The tri-dimensional AgInS/InS co-modified TiO nanobush superstructure photoanode possesses superior photoelectric cathodic protection characteristic for pure cooper whose self-corrosion potential is more negative in simulated marine environment under simulated solar light illumination.[Figure not available: see fulltext.].