3D ZnIn2S4 nanosheet/TiO2 nanowire arrays and their efficient photocathodic protection for 304 stainless steel
By Sun, Wenxia; Wei, Na; Cui, Hongzhi; Lin, Yuan; Wang, Xinzhen; Tian, Jian; Li, Jian; Wen, Jing
Published in Applied Surface Science
2018
Abstract
A well-designed heterostructure engineered ZnIn2S4 nanosheet/TiO2 nanowire arrays photoanode is investigated for photocathodic protection. The ZnIn2S4 nanosheets are distributed uniformly on the surface of the TiO2 nanowire by a hydrothermal method. The stem-and-leaf-like ZnIn2S4 nanosheet/TiO2 nanowire arrays exhibit excellent photoelectrochemical properties, owing to the energy band structure and large surface area. A maximum photocurrent density of 2mAcm?2 is achieved for the ZnIn2S4 nanosheet/TiO2 nanowire composite film for a 6h reaction time under white illumination. Moreover, the potential of the 304 stainless steel coupled with the composite film immediately shifts negatively to ?1.17V (vs. SCE), which is significantly lower than the corrosion potential (?0.201V vs. SCE). Thus, the composite film offers a superior photocathodic protection for stainless steel against corrosion by a NaCl solution. This study provides a promising approach for the design and synthesis of composite films with enhanced photoelectrochemical performance.