Transition-Metal Oxide (111) Bilayers

Two-dimensional transition metal honeycomb realized: Hf on Ir(111).

Two-dimensional (2D) honeycomb systems made of elements with d electrons are rare. Here, we report the fabrication of a transition metal (TM) 2D layer, namely, hafnium crystalline layers on Ir(111). Experimental characterization reveals that the Hf layer has its own honeycomb lattice, morphologically identical to graphene. First-principles calculations provide evidence for directional bonding b...

Antimicrobial Effect of Transition Metal Oxide Nanoparticles

Band offsets in transition-metal oxide heterostructures

We measured valence band offsets in Ta2O5–WO3, Ta2O5–Nb2O5 and WO3–Nb2O5 heterostructure couples by in situ x-ray photoelectron spectroscopy, immediately following the bi-layer growth in ultra-high vacuum. Conduction band offsets were estimated using the measured valence band offsets in conjunction with the literature values for the respective band gaps. The offsets between Ta2O5 and WO3 and be...

Transition-metal doped zinc oxide nanowires.

The introduction of impurity atoms into semiconducting materials is the primary method for controlling the properties of the semiconductor, such as band gap or electrical conductivity. This practice is routinely performed with bulk semiconductors and, more recently, has been extended to nanoscale semiconductors as well. In particular, II–VI and III–V semiconductors that have been doped with tra...

Quantum spin Hall effect in a transition metal oxide Na2IrO3.

We study theoretically the electronic states in a 5d transition metal oxide Na2IrO3, in which both the spin-orbit interaction and the electron correlation play crucial roles. A tight-binding model analysis together with the first-principles band structure calculation predicts that this material is a layered quantum spin Hall system. Because of the electron correlation, an antiferromagnetic orde...