Growth of ZnO hexagonal nanoprisms

Abstract

We show the success of large-scale growth of ZnO hexagonal nanoprisms on silicon substrates by a two-staged mechanism. In the first stage, the catalyst nanoparticles assisted the nucleation via the vapour-liquid-solid (VLS) mechanism to form polyhedral nanoparticles. In the second stage, the nanoprism was grown up by anisotropic homoepitaxy, layer by layer, on the c-face of the polyhedral nanoparticle. The surface of the nanoprism consists of the ultraflat {0001} and {10 10} planes. The nanoprism is 200-500 nm in width and controllably sized in length, of high crystalline quality and excellent optical quality. This nanoprism would be an interesting building block for highly efficient nanolasers.

Site-specific nucleation and controlled growth of a vertical tellurium nanowire array for high performance field emitters

“…The growth of pyramids is kinetically favored and faster along the (001) direction and slower along the (010) and (100) faces of the Te crystal planes. The anisotropic growth of Te is consistent with the Bravais-Friedel law that high index crystal planes with small interplanar spacing grow faster than low index planes [25]. The repetition of nucleation and anisotropic growth on the c-face of a pre-grown Te pyramid under different supersaturating, flux, temperature and kinetics generates final morphologies of Te nanostructures as shown in figure 1.…”

“…It is believed that nucleation of a second pyramid is activated before the full growth of the previous one, provided that the c-face has grown larger than the critical island size for nucleation. This process is called the Ehrlich-Schwoebel (ES) barrier effect, as adspecies on the nucleated island experience a barrier to diffusion over the island edges, then the next atomic layer nucleates before the completion of previous one [25][26][27]. Te growth under the The schematic growth mechanism in figure 4(e) describes the formation of Te structures, islands grow by continuous addition of atoms to the slope, leaving behind a new section of c-face at the top of the island.…”

Synthesis of location‐dependent phosphorus‐doped ZnO nanostructures on the porous alumina membranes

“…Furthermore, the side wall of nanorods shows a mound‐like structure in Fig. d, suggesting the existence of an Ehrlich–Schwoebel barrier (ESB) in the 001 ZnO surface . The ESB is an energy barrier for adspecies to jump from a higher terrace to a lower one at the edge of step, which also affects the growth of nanorods.…”

Synthesis and Characterization of Flower‐Like Bundles of ZnO Nanosheets by a Surfactant‐Free Hydrothermal Process

“…Recently, ZnO nanostructure, with a wide direct band gap and strong excitonic binding energy, has attracted much attention because of its promising characteristics for applications in electronic, photonic, and spintronic nanodevices. So far, various ZnO nanostructures, including nanowires [5], nanorods [6], nanonails [7], nanobridges [7], nanoprisms [8], nanotubes [9], nanobelts [3], nanorings [10], nanowhiskers [11], nanocombs [12,13], nanohelixes [14], nanosprings [14], nanopropeller [15], nanobows [16], nanocages [17], nanodisk [18], nanopoins [19], and nanopores [20], have been fabricated by using vapor-phase process and solution phase route. Vapor-phase process such as molecular beam epitaxy (MBE) [21], metal-organic chemical vapor deposition (MOCVD) [22], sputtering method [23], pulsed laser deposition (PLD) [24], infrared irradiation [25], thermal decomposition [26], and thermal evaporation and condensation [27] is favored for their simplicity and high quality products.…”