# Colloidal Hollandite Holey Rods Produced by Presynthetic Nanohybridization

## TL;DR

Scientists created hollow rod-shaped nanomaterials using a hybrid of titanium dioxide and iron oxide, which could be useful for synthesis and environmental cleanup.

## Contribution

A novel presynthetic nanohybridization method was developed to produce colloidal hollow rods with controlled morphology at low temperatures.

## Key findings

- Hollow rods with cavity diameters of about 100 nm were produced at 800 °C.
- The rods showed colloidal stability in water, likely due to their nanotube origin.
- The method allows for controlled synthesis through parameters like KCl concentration and Fe/Ti ratio.

## Abstract

Electrostatically stabilized binary hybrids comprising
TiO2 nanotubes and Fe2O3 nanoparticles
were
self-assembled and investigated as precursors for a KFTO material.
Presynthetic nanohybridization is a way to organize the components,
with the caveat that the mere nanomaterial combination cannot grant
a high degree of control due to their general susceptibility to aggregation,
resulting in masses with poor spatial order. Various hybridization
conditions were explored, and the effects of the experimental parameters
were investigated in detail, considering KCl concentration, Fe/Ti
ratio, and hydrothermal treatment temperature. The optimized synthetic
product was obtained at a remarkably low temperature (800 °C),
and it was characterized by small size, partially hollow morphology
(cavity diameter ca. 100 nm), and water colloidal stability, likely
inherited from the parent nanotubes. These hollow rods can be envisioned
as nanoreactors for confined space synthesis and as tools for environmental
remediation.