Double-walled structure of anodic TiO2 nanotubes in H3PO4/NH4F mixed electrolyte. (25th April 2018)

• Record Type: Journal Article
• Authors: Chen, Siyu; Chen, Ying; Li, Chengyuan; Ouyang, Huijun; Qin, Shuai; Song, Ye
• Is Part Of: Materials research express. Volume 5:Number 4(2018)
• Publication Date: 2018-04-25
• Subjects: anodization -- H3PO4 -- double-walled structure -- annealing; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/aabdd2
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: Normally, the well-ordered anodic TiO2 nanotubes (ATNTs) are obtained in NH4 F electrolyte, after annealing, the double-walled structure of nanotubes will appear. Here, after adding H3 PO4 into NHF4 electrolyte, we got the double-walled structure of nanotubes by anodizing without annealing, which means the direct existence of anion-contaminated layer in ATNTs. Influence of H3 PO4 content on anodizing voltage and morphology of ATNTs were compared in detail. The XRD pattern illustrated that the crystallinity decreases with increasing H3 PO4 concentration, and the anion-contaminated layer thickens with the increase of H3 PO4 concentration. Meanwhile, the existence of the anion-contaminated layer also proved the limitations of the filed-assisted dissolution theory, while the double-walled structure can be explained by oxygen bubble model and plastic flow model.