Unveiling the Thermal and Aqueous Stability of 1D Lepidocrocite Titania

TL;DR

This study investigates the thermal and aqueous stability of 1D lepidocrocite titania filaments, revealing their structural changes under heat and water exposure, and establishing stability thresholds for practical applications.

Contribution

It provides detailed insights into the stability limits of lepidocrocite titania filaments under various conditions, informing their potential use in technological applications.

Findings

Retain lepidocrocite structure up to 300°C

Amorphization occurs at filament overlaps upon heating

Aqueous storage induces transformation into anatase nanoparticles

Abstract

One dimensional lepidocrocite titanium dioxide filaments are investigated with respect to their thermal and aqueous stability. Structural and phase evolution are examined using in situ heating in vacuum within transmission electron microscopy combined with electron energy loss spectroscopy, and at ambient conditions using Raman spectroscopy. The filaments retain their lepidocrocite structure up to 300 degree and above which localized sintering and amorphization occur at filament overlap junctions. With further heating, the amorphous regions crystallize into anatase, with Raman spectroscopy corroborating the onset of structural disorder. Long term aqueous storage up to 100 days at ambient conditions induces transformation into flake like anatase nanoparticles. This process is strongly suppressed under refrigerated storage, where no structural changes are observed over the same period. These results establish critical thermal and environmental stability thresholds that define operational advantages and limits for emerging applications of 1D lepidocrocite filaments.