Zinc selenide nanoribbons and nanowires were obtained using laser ablation of ZnSe pressed powders. Their formation appeared to follow the vapor−solid and vapor−liquid−solid growth mechanisms, respectively. The product was characterized by means of scanning electron microscopy, transmission electron microscopy, micro-Raman scattering, and energy-dispersive X-ray spectroscopy. The ZnSe nanoribbons had a perfect wurtzite-2H single-crystal structure with a [120] growth direction and the {001} close-packed lattice planes of hexagonal ZnSe stacking along the nanoribbon width axis. The ZnSe nanowires grew with the {001} close-packed lattice planes of the wurtzite-2H structure stacking along the nanowire length axis. Both the longitudinal optic (LO) and transverse optic (TO) phonon peaks of the ZnSe nanowires and nanoribbons showed a clear shift toward low frequency relative to bulk values, probably because of small size and large surface effects. The ZnSe nanostructures exhibited strong self-activated luminescence centered at 596 nm.

Electrical properties of ZnO nanowires and intramolecular p–n junctions were characterized by I–V measurements. These nanowires were grown embedded in anodic aluminum oxide (AAO) templates by vapor-phase-transport growth method. The nanowires were dense, continuous, and uniform in diameter along the length of the wires. I–V measurements showed the average resistivity of the ZnO nanowires in AAO templates was about one order of magnitude higher than that of the naked single ZnO nanowire. The p–n junctions in ZnO nanowires were fabricated by a two-step growth of ZnO with and without dopant of boron (∼1 wt %) in the source. I–V results suggested that p–n junctions in ZnO nanowires were formed by the two-step method.

Tungsten oxide is one of the most important transition metal oxide materials, which possesses some unique properties such as electrochromic, optochromic, and gaschromic properties. In this paper, we report a simple method for synthesizing high quantity tungsten oxide nanoribbons by oxidizing a tungsten plate under moist conditions. Using potassium iodide as the catalyst, tungsten oxide nanoribbons with a thickness of 40-100 nm, width up to 1 µm and length up to hundreds of micrometres are obtained on a large scale. The morphology, composition and crystal structure of the nanoribbons are characterized by various methods, such as scanning electron microscopy, transmission electron microscopy and x-ray diffraction. The nanoribbons comprise mainly monoclinic tungsten trioxide (WO 3 ) growing along the [001] direction and the orthorhombic WO 3 (H 2 O) 0.33 . The measured lattice parameters are β = 89.93 • , a = 0.7274 nm, b = 0.7501 nm, c = 0.3824 nm for WO 3 and a = 0.7359 nm, b = 1.251 nm, c = 0.7704 nm for WO 3 (H 2 O) 0.33 , respectively.

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