Oxygen Vacancies in Oxide Nanoclusters: When Silica Is More Reducible Than Titania.

Oxygen vacancies are related to specific optical, conductivity and magnetic properties in macroscopic SiO and TiO compounds. As such, the ease with which oxygen vacancies form often determines the application potential of these materials in many technological fields. However, little is known about the role of oxygen vacancies in nanosized materials.

Properties of hydrated TiO and SiO nanoclusters: dependence on size, temperature and water vapour pressure.

Nanoscale titania (TiO) and silica (SiO) are massively produced technologically important nanomaterials used in a wide range of technological applications where nano-titania is the active component (e.g. water splitting, pollution remediation, self-cleaning coatings).

Stability of mixed-oxide titanosilicates: dependency on size and composition from nanocluster to bulk.

Nanostructured titanosilicate materials based upon interfacing nano-TiO with nano-SiO have drawn much attention due to their huge potential for applications in a diverse range of important fields including gas sensing, (photo)catalysis, solar cells, photonics/optical components, tailored multi-(bio)functional supports and self-cleaning coatings. In each case it is the specific mixed combination of the two SiO and TiO nanophases that determines the unique properties of the final nanomaterial. In the bulk, stoichiometric mixing of TiO with SiO is limited by formation of segregated TiO nanoparticles or metastable glassy phases and more controlled disperse crystalline mixings only occur at small fractions of TiO (<15 wt%).

Predicting size-dependent emergence of crystallinity in nanomaterials: titania nanoclusters versus nanocrystals.

Bottom-up and top-down derived nanoparticle structures refined by accurate ab initio calculations are used to investigate the size dependent emergence of crystallinity in titania from the monomer upwards. Global optimisation and data mining are used to provide a series of (TiO) global minima candidates in the range N = 1-38, where our approach provides many new low energy structures for N > 10. A range of nanocrystal cuts from the anatase crystal structure are also considered up to a size of over 250 atoms.