Fig. 1.

Simplified schematic representation of fabrication techniques for TiO₂ nanomaterials. a Non-spherical, hollow, and magnetically loaded particles fabricated through a template-assisted, bottom-up strategy. Adapted from Ref. [49] with permission from the John Wiley & Sons. b The hydrothermal approach is one of the bottom-up strategies for the fabrication of a wide range of one-dimensional TiO₂ NSs. The TiO₂ precursor, temperature, and incubation time determine the final nanostructure. Adapted from Ref. [55] with permission from the Springer Nature. c Well-aligned and ordered TiO₂ nanotubes can be fabricated through a top-down strategy based on electrochemical anodization. Adapted from Ref. [74] with permission from the American Chemical Society