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Assessing Disaster Resilience of Concrete with Titanium Dioxide Nanoparticles
Published on: November 14, 2025
308
Structural evolution of titanium dioxide during reduction in high-pressure hydrogen.
Sencer Selcuk1, Xunhua Zhao2, Annabella Selloni2
1Department of Chemistry, Princeton University, Princeton, NJ, USA. sselcuk@princeton.edu.
Nature Materials
|July 18, 2018
Summary
Hydrogenation creates black titanium dioxide (TiO₂) with a disordered shell, enhancing visible light absorption for photocatalysis. This study elucidates the formation mechanism of this advanced material.
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Titanium dioxide (TiO₂) exhibits excellent photocatalytic activity under UV light.
- Extending TiO₂ photoactivity to the visible spectrum is crucial for broader applications.
- Black TiO₂, produced by hydrogenation, shows enhanced visible light absorption.
Purpose of the Study:
- To elucidate the formation mechanism of black TiO₂.
- To understand the structural features responsible for visible light absorption.
- To investigate the role of surface disorder in black TiO₂ photocatalysis.
Main Methods:
- First-principles-validated reactive force field molecular dynamics simulations.
- Simulations of anatase TiO₂ surfaces and nanoparticles under high temperature and hydrogen pressure.
- Analysis of oxygen vacancy diffusion and subsurface migration barriers.
Main Results:
- Identified surface oxygen vacancy formation and diffusion as key to black TiO₂.
- Revealed high migration barriers on {001} facets leading to surface disordering.
- Confirmed the disordered, hydrogenated amorphous shell's role in visible light photoactivity.
Conclusions:
- The formation of black TiO₂ involves surface disordering driven by oxygen vacancy migration.
- The disordered shell is critical for visible light absorption in black TiO₂.
- Insights gained are relevant to understanding disordered surfaces in photocatalytic water-splitting.
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