Direct Z-scheme MgIn2S4/TiO2 heterojunction for enhanced photocathodic protection of metals under visible light. (28th January 2022)

• Record Type: Journal Article
• Authors: Li, Hong; Cui, Xingqiang; Song, Weizhe; Yang, Zhanyuan; Li, Yanhui; Zhang, Pengfei; Zheng, Zongmin; Wang, Yuqi; Li, Junru; Ma, Fubin
• Is Part Of: Nanotechnology. Volume 33:Number 16(2022)
• Publication Date: 2022-01-28
• Subjects: TiO2 -- MgIn2S4 -- photocathodic protection -- Z-scheme -- ESR; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/ac493c
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: To improve the photocathodic protection performance of traditional TiO2 photoanodes for metals, constructing a Z-scheme heterojunction is one of the most promising and creative strategies. Herein, we fabricated a novel Z-scheme MgIn2 S4 nanosheets/TiO2 nanotube nanocomposite through anodization and hydrothermal method. The optimized Z-scheme MgIn2 S4 /TiO2 nanocomposites exhibited stronger visible light absorption, higher separation efficiency of photoelectrons and photocathodic protection performances in comparison to pure TiO2 . The theoretical analysis and experimental results show that the Z-scheme heterojunction and oxygen vacancies jointly improved the separation efficiency of photogenerated electron–hole pairs and visible light absorption capacity, thereby improving the photoelectric conversion performance of the MgIn2 S4 /TiO2 nanocomposites. Furthermore, the influence of the precursor solution concentration on the photocathodic protection performances of the composites was investigated. As a result, when the concentration of magnesium source in the precursor solution was 0.06 mmol, the prepared MgIn2 S4 /TiO2 -0.06 displayed the best photocathodic protection performance. In addition, the hydroxyl radicals (·OH) generated in the electron spin resonance (ESR) experiment verified the Z-scheme heterojunction mechanism of the MgIn2 S4 /TiO2 composite, and also demonstrated the excellent redox performance of the composite. This work provides valuable reference for the construction of high-performance Z-scheme heterojunctions for photocathode protection of metals.