Figure 1

(a) Large area STM image ($62\mathrm{nm}\times 62\mathrm{nm}$; bias $\mathrm{voltage}=0.48\mathrm{V}$; $I_T=1.4\mathrm{nA}$) of a single-domain lepidocrocite nanosheet on $(1\times 2)\mathrm{\text{−}}\mathrm{Pt}(110)$. The central brighter area is separated from the lower terrace by a substrate monoatomic step. Inset: ($14\times 4$) LEED pattern. (b) High resolution STM image ($13.7\mathrm{nm}\times 13.7\mathrm{nm}$; bias $\mathrm{voltage}=0.28\mathrm{V}$; $I_T=1.65\mathrm{nA}$) of the nanosheet. The overlayer (superstructure) unit cell is indicated by the small (large) rectangle. Inset: Tersoff-Hamann simulation of the STM image with superimposed solid sphere model (see text) (oxygen: dark gray/red, titanium: light gray/blue). Dark stripes along [001] are due to overlayer bending toward the substrate (see the interface side view in the [001] plane, lower left corner; Pt: large, gray). (c),(d) High resolution STM images of the nanosheet. ($13.6\mathrm{nm}\times 13.6\mathrm{nm}$; bias $\mathrm{voltage}=0.42\mathrm{V}$; $I_T=0.9\mathrm{nA}$ and $18.0\mathrm{nm}\times 18.0\mathrm{nm}$; bias $\mathrm{voltage}=1.80\mathrm{V}$; $I_T=1.0\mathrm{nA}$).Reuse & Permissions

Figure 2

Experimental XPD $2\pi$ plots (left) and SSC-SW simulations based on the DFT model (right) of Ti $2p$ and O $1s$ core levels from a lepidocrocite nanosheet on $(1\times 2)\mathrm{\text{−}}\mathrm{Pt}(110)$. Intensity: white, maximum; black, minimum.Reuse & Permissions

Figure 3

(a) Top and side views of an unsupported anatase (001) bilayer (dark gray/red: oxygen; light gray/blue: titanium). (b) Top and side views of an unsupported lepidocrocite nanosheet, obtained from (a) by sliding the upper ML with respect to the lower one by half a unit cell along [100] [as indicated by the ellipse in (a); see text]. (c) Bulk unit cell of anatase ${\mathrm{TiO}}_2$. (d) DFT formation energy from the bulk vs the lattice parameter along [100] for the $(\mathrm{a})\to (\mathrm{b})$ structural transition.Reuse & Permissions