Templated synthesis of TiO2 nanotube macrostructures and their photocatalytic properties

• Published in: Nano research 2015-03, Vol.8 (3), p.900-906
• Main Authors: Li, Hongbian, Zhou, Qiaoyu, Gao, Yuntian, Gui, Xuchun, Yang, Long, Du, Mingde, Shi, Enzheng, Shi, Jidong, Cao, Anyuan, Fang, Ying
• Format: Article
• Language: English
• Subjects: Arrays; Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Carbon; Chemical vapor deposition; Chemistry and Materials Science; Condensed Matter Physics; Energy conversion; Fabrication; Materials Science; Nanotechnology; Photocatalysis; Research Article; Scanning electron microscopy; Solar energy; Titanium dioxide; Wastewater treatment
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-014-0571-3

Controlled synthesis of hierarchically assembled titanium dioxide (TiO 2 ) nanostructures is important for practical applications in environmental purification and solar energy conversion. We present here the fabrication of interconnected TiO 2 nanotubes as a macroscopic bulk material by using a porous carbon nanotube (CNT) sponge as a template. The basic idea is to uniformly coat an amorphous titania layer onto the CNT surface by the infiltration of a TiO 2 precursor into the sponge followed by a subsequent hydrolysis process. After calcination, the CNTs are completely removed and the titania is simultaneously crystallized, which results in a porous macrostructure composed of interconnected anatase TiO 2 nanotubes. The TiO 2 nanotube macrostructures show comparable photocatalytic activities to commercial products (AEROXIDE TiO 2 P25) for the degradation of rhodamine B (RhB). Moreover, the TiO 2 nanotube macrostructures can be settled and separated from water within 12 h after photocatalysis, whereas P25 remains suspended in solution after weeks. Thus the TiO 2 nanotube macrostructures offer the advantage of easy catalyst separation and recycle and can be a promising candidate for wastewater treatment.