Pressure-induced amorphization and polyamorphism in one-dimensional single crystal TiO2 nanomaterials

TL;DR

This study demonstrates pressure-induced amorphization and polyamorphism in one-dimensional TiO2 nanoribbons, revealing new phase transition behaviors and providing a novel method for synthesizing amorphous nanomaterials.

Contribution

It is the first to show pressure-induced amorphization and polyamorphism in 1D TiO2 nanomaterials, offering insights into phase transition mechanisms and synthesis methods.

Findings

Pressure-induced amorphization occurs in TiO2-B nanoribbons.

HDA form relates to baddeleyite structure.

LDA form has an {\

Abstract

The structural phase transitions of single crystal TiO2-B nanoribbons were investigated in-situ at high-pressure using the synchrotron X-ray diffraction and the Raman scattering. Our results have shown a pressure-induced amorphization (PIA) occurred in TiO2-B nanoribbons upon compression, resulting in a high density amorphous (HDA) form related to the baddeleyite structure. Upon decompression, the HDA form transforms to a low density amorphous (LDA) form while the samples still maintain their pristine nanoribbon shape. HRTEM imaging reveals that the LDA phase has an {\alpha}-PbO2 structure with short range order. We propose a homogeneous nucleation mechanism to explain the pressure-induced amorphous phase transitions in the TiO2-B nanoribbons. Our study demonstrates for the first time that PIA and polyamorphism occurred in the one-dimensional (1D) TiO2 nanomaterials and provides a new method for preparing 1D amorphous nanomaterials from crystalline nanomaterials.