物理化学学报 >> 2019, Vol. 35 >> Issue (11): 1232-1240.doi: 10.3866/PKU.WHXB201901025

论文 上一篇    下一篇

ZnSe/MoO3/TiO2复合膜的制备及其光生阴极保护效应

王海鹏1,官自超1,王霞1,金飘1,许慧1,陈丽芳1,宋光铃2,*(),杜荣归1,*()   

  1. 1 厦门大学化学化工学院化学系,福建 厦门 361005
    2 厦门大学材料学院,海洋材料腐蚀防护研究中心,福建 厦门 361005
  • 收稿日期:2019-01-09 录用日期:2019-02-26 发布日期:2019-03-14
  • 通讯作者: 宋光铃,杜荣归 E-mail:guangling.song@hotmail.com;rgdu@xmu.edu.cn
  • 基金资助:
    国家自然科学基金(21573182);国家自然科学基金(51731008);国家自然科学基金(51671163);国家自然科学基金(21621091);国家自然科学基金(J1310024)

Fabrication of a ZnSe/MoO3/TiO2 Composite Film Exhibiting Photocathodic Protection Effect

Haipeng WANG1,Zichao GUAN1,Xia WANG1,Piao JIN1,Hui XU1,Lifang CHEN1,Guangling SONG2,*(),Ronggui DU1,*()   

  1. 1 Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
    2 Center for Marine Materials Corrosion and Protection, College of Materials, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
  • Received:2019-01-09 Accepted:2019-02-26 Published:2019-03-14
  • Contact: Guangling SONG,Ronggui DU E-mail:guangling.song@hotmail.com;rgdu@xmu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21573182);the National Natural Science Foundation of China(51731008);the National Natural Science Foundation of China(51671163);the National Natural Science Foundation of China(21621091);the National Natural Science Foundation of China(J1310024)

摘要:

针对TiO2半导体不能有效吸收可见光,光电转换效率较低等问题,可通过对TiO2半导体进行修饰和改性,制备TiO2复合材料,提高其光电化学性能。因此,本工作以Ti表面制备的TiO2纳米管膜为基础,分别应用循环伏安电沉积法和脉冲电沉积法在膜表面先后沉积MoO3和ZnSe颗粒,获得具有级联能带结构的ZnSe/MoO3/TiO2纳米管复合膜,并将其应用于对403不锈钢(403SS)实施光生阴极保护。相较于纯TiO2纳米管膜,紫外-可见(UV-Vis)吸收光谱和光致发光(PL)谱测试表明,ZnSe/MoO3/TiO2复合膜的吸收边红移,在可见光区具有良好的光吸收性能,光生载流子复合得到更有效抑制。光电化学测试表明,白光照射下,处于0.5 mol·L−1 KOH溶液中的ZnSe/MoO3/TiO2复合膜的光电流密度达到了同条件下纯TiO2膜的2倍,可使与之耦连的浸泡于0.5 mol·L−1 NaCl溶液中的403SS电极电位下降470 mV,显示出良好的光生阴极保护效应。复合膜还具有一定的储能特性,在光照后又转为暗态的22.5 h内仍对403SS具有一定阴极保护作用。

关键词: 阳极氧化, 电沉积, TiO2纳米管, 不锈钢, 光电化学性质, 光生阴极保护

Abstract:

TiO2 is a semiconductor material with excellent photoelectrochemical properties that can provide photocathodic protection for metals. However, TiO2 can only absorb ultraviolet (UV) light at wavelengths of < 380 nm because of its wide band gap. In addition, photo-induced electron-hole pairs in the TiO2 semiconductor easily recombine, which leads to a low photoelectric conversion efficiency. Another shortcoming is that pure TiO2 semiconductors cannot sustain photocathodic protection in the dark, which may limit their practical applications to provide photocathodic protection. To address these shortcomings, various modification methods have been established by preparing TiO2 composite materials to improve their photoelectrochemical properties. In this study, a ZnSe- and MoO3-modified TiO2 nanotube composite film with charge storage ability was prepared to enhance its photocathodic protection effect on stainless steel. A TiO2 nanotube array film was prepared on a Ti foil via anodic oxidation and then MoO3 and ZnSe particles were deposited onto the film by cyclic voltammetry and pulse electrodeposition, respectively, to afford a ZnSe/MoO3/TiO2 nanotube composite film having a cascade band structure. Scanning electron microscopy observations showed that the TiO2 film consisted of ordered nanotubes with an average inner diameter of approximately 100 nm and wall thickness of approximately 15 nm. This nanotube structure remained intact after MoO3 and ZnSe particle deposition on the film. Energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses indicated that the prepared nanotube composite film was composed of ZnSe, MoO3, and TiO2. The UV-Vis absorption and photoluminescence spectra showed that the photoresponse of the composite film was extended to the visible light region and the photo-induced electron-hole pair recombination was reduced. Photoelectrochemical and electrochemical measurements indicated that the photocurrent intensity of the composite film in a 0.5 mol·L−1 KOH solution was two-fold higher than that of the pure TiO2 film. Under white light illumination, the ZnSe/MoO3/TiO2 composite film decreased the potential of the coupled 403 stainless steel (403SS) in a 0.5 mol·L−1 NaCl solution by 470 mV (relative to the corrosion potential), demonstrating an effective photocathodic protection effect. It should be noted that the composite film exhibited a charge storage capability and could continuously provide cathodic protection for 22.5 h after illumination was stopped. In addition, electrochemical impedance spectroscopy results indicated that the composite film significantly decreased the charge transfer resistance of the coupled 403SS, highlighting the photocathodic protection effect on 430SS.

Key words: Anodic oxidation, Electrochemical deposition, TiO2 nanotube, Stainless steel, Photoelectrochemical property, Photocathodic protection