Synthesis and characterization of anatase TiO2 nanotubes with controllable crystal size by a simple MWCNT template method

► Highly crystalline and stable phase-pure anatase TiO2 nanotubes were produced by a simply MWCNT template method. ► A homogeneous thin coating layer of TiO2 on the surface of MWCNTs could be obtained. ► Small crystal size of anatase is formed at lower temperatures and higher temperatures cause significant increase of crystal size from 8 to 24 nm. ► Convex closed tip structure of TiO2 nanotubes is formed owing to the good coating of TiO2.