Theory of Ferromagnetism in Reduced ZrO Nanoparticles.

Bulk ZrO is both nonreducible and nonmagnetic. Recent experimental results show that dopant-free, oxygen-deficient ZrO nanostructures exhibit a ferromagnetic behavior at room temperature (RT). Here, we provide a comprehensive theoretical foundation for the observed RT ferromagnetism of zirconia nanostructures.

TiO and ZrO in biomass conversion: why catalyst reduction helps.

Biomass refers to plant-based materials that are not used for food or feed. As an energy source, lignocellulosic biomass (lignin, cellulose and hemicellulose) can be converted into various forms of biofuel using thermal, chemical and biochemical methods. Chemical conversion implies the use of solid catalysts, usually oxide materials.

Reduction of Hydrogenated ZrO Nanoparticles by Water Desorption.

Reduction of zirconia by water desorption from a hydrogenated surface is the topic of this study. The focus is on the role of nanostructuring the oxide reducibility measured by the cost of formation of oxygen vacancies by water desorption. We have performed density functional theory calculations using the Perdew-Burke-Ernzerhof + approach and including dispersion forces on the adsorption, dissociation, diffusion of hydrogen on the ZrO (101) surface and on ZrO, ZrO, and ZrO nanoparticles (NPs).

Reducibility of ZrO/PtZr and ZrO/Pt 2D films compared to bulk zirconia: a DFT+U study of oxygen removal and H adsorption.

Oxide reducibility is an important property that determines the chemical and physical behavior of the materials under working conditions. Zirconia is a non-reducible oxide that exhibits high resistance to the loss of oxygen and low reactivity towards hydrogen, two typical processes involved in oxide reduction. Oxide reducibility can change substantially by nanostructuring (e.

Tuning the charge state of Ag and Au atoms and clusters deposited on oxide surfaces by doping: a DFT study of the adsorption properties of nitrogen- and niobium-doped TiO2 and ZrO2.

The charge state of Ag and Au atoms and clusters (Ag4 and Au4, Ag5 and Au5) adsorbed on defective TiO2 anatase(101) and tetragonal ZrO2(101) has been systematically investigated as a function of oxide doping and defectivity using a DFT+U approach. As intrinsic defects, we have considered the presence of oxygen vacancies. As extrinsic defects, substitutional nitrogen- and niobium-doping have been investigated, respectively.