Highly Efficient Photocathodic Protection Performance of ZIS@CNNs Composites under Visible Light

Abstract

Low isolation efficiency of photogenerated electron-hole pairs and inadequate utilization of visible light limit the application of g-C3N4 nanosheets (CNNs) in photocathodic protection (PCP). Therefore, indium zinc sulfide (ZnIn2S4, ZIS) nanolayers with nano-leaf structures were fabricated on CNNs using a simple hydrothermal method and used as visible light sensitizer and electron donor to improve its PCP performance. Under visible light illumination, the 30% ZIS@CNNs photoelectrode coupled with 316 stainless steel (SS) exhibited the largest photocurrent density of 17.30 μA cm−2 and the highest potential drop of 0.37 V, which was approximately 4 and 7.5 times higher than that of pure CNNs, respectively. The improvement in protection performance may be attributable to the crucial increase in visible light absorption and the terrific enhancement in rapid migration pathways provided using heterogeneous junctions.