Vertically oriented pure BiVO₄ and Mo-doped BiVO₄ nanoworm array films with a diameter of about 100 nm were prepared using the pulsed laser deposition (PLD) technique.

The analysis and density-functional tight-binding simulations of possible configurations of silicon nanowires (SiNWs) enclosed by low-index surfaces reveal a number of remarkable features. For wires along ⟨100⟩, ⟨110⟩, and ⟨111⟩ directions, many low-index facet configurations and cross sections are possible, making their controlled growth difficult. The ⟨112⟩ wires are the most attractive for research and applications because they have only one configuration of enclosing low-index facets with a rectangular cross section, enclosed with the most stable (111) facet and the (110) facet next to it. In general, the stability of the SiNWs is determined by a balance between (1) minimization of the surface energy γ(111)<γ(110)<γ(001), and (2) minimization of the surface-to-volume ratio [svr; svr(hexagonal)>svr(rectangular)>svr(triangular)]. The energy band gaps follow the order of ⟨100⟩wires>⟨112⟩wires>⟨111⟩wires>⟨110⟩wires. The results are compared with our recent scanning tunneling microscopy and transmission electron microscopy data.