Enhancing photocathodic protection of Q235 carbon steel by co-sensitizing TiO2 nanotubes with CdIn2S4 nanogranules and WO3 nanoplates
Jinke Zhu, Xuan Zhang, Zhanyuan Yang, Xiang‐Yu Zhang, Yanhui Li, Da Li, Hong Li
Abstract
In order to improve the photocathodic protection (PCP) performance of TiO 2 and its continuous protection ability in the dark, we designed and prepared CdIn 2 S 4 /WO 3 /TiO 2 (C/W/T) photoanodes through sequentially depositing WO 3 nanoplates (NPs) and CdIn 2 S 4 nanogranules (NGs) on TiO 2 nanotubes (NTs) by simple hydrothermal method . The effect of hydrothermal time on the PCP performances of C/W/T for Q235 carbon steel (CS) was studied. The PCP performance of C/W/T was compared with that of pure TiO 2 , CdIn 2 S 4 /TiO 2 (C/T) and WO 3 /TiO 2 (W/T). When the hydrothermal time for preparing WO 3 NP S and CdIn 2 S 4 NGs was both 6 h, the prepared C/W/T possessed the optimal PCP performance. The photogenerated potential drop of C/W/T could reach 490 mV vs. SCE. The C/W/T exhibited higher photocurrent density (633 μA·cm −2 ) and lower charge transfer resistance (11.34 Ω·cm 2 ) than bare TiO 2 , C/T and W/T. The electron storage capacity of C/W/T was 2.88 times that of C/T, which may be attributed to the electronic storage properties of WO 3 NPs. In addition, C/W/T can provide continuous protection for Q235 CS for up to 10 h in the dark. This work provides a new idea for designing energy storage photoanode materials with good PCP properties.