Efficient photocathodic protection of nanoflower MgIn2S4-modified CNNs composites on 316 SS under visible light

Numerous drawbacks limit the use of g-C3N4 nanosheets (CNNs) in photocathode protection (PCP) applications, such as poor specific surface area, low carrier separation efficiency, and weak absorption of visible light. The introduction of MgIn2S4 (MIS) creates a heterojunction with the CNNs, which greatly improves carrier separation efficiency. CNNs were hydrothermally attached to the MIS nanoflowers. Compared to pure CNNs, the PCP performances of MIS/CNNs composites on 316 stainless steel (SS) were significantly improved. Under visible illumination, the 10% MIS/CNNs photoconductive electrodes showed a maximum photoinduced current density of 31.40 mu A cm -1 and a photoinduced potential drop of 0.34 V, which were 2.1 and 8.5 times higher than those of pure CNNs, respectively. The improved protection performance could be attributed to the significant increase in the absorption of visible light and the greatly enhanced efficiency of the photoinduced separation of electrons and holes.