Self-catalytic synthesis and photoluminescence of ZnO nanostructures on ZnO nanocrystal substrates

Abstract

ZnO tetrapods and ZnO nanorods were synthesized on ZnO nanocrystal substrates by a vapor transport process. The source materials were ZnCO3 powder and ZnO powder, respectively, which were reduced by graphite powder to yield different amounts of the vapor. The catalysts were ZnO nanocrystal layers prepared by successive ionic layer adsorption and reaction method. The effect of the source materials on the structure was investigated. Results showed that for the source of ZnCO3 powder, ZnO tetropds constituted by the four pillarlike ZnO nanorods were obtained, while for the source of ZnO powder a nanorods array was formed. Possible growth mechanism and room-temperature photoluminescence of ZnO nanostructures are discussed.

ZnO Tetrapods: Synthesis and Applications in Solar Cells

“…The growth mechanism of ZnO tetrapods is still a subject of debate [52][53][54][55]. The factors affecting the morphologies of the tetrapod nanostructures and the possibility of controlling the tetrapod ZnO nanostructures during synthesis under suitable reaction conditions remain unclear.…”

Hydrothermal technology for nanotechnology

“…In recent years ZnO nanostructures have attracted much attention due to their exceptional properties compared with bulk materials. A variety of morphologies have been demonstrated for ZnO nanostructures such as nanoparticles [62], nanowires [63,64], nanorods [65,66], tetrapod nanowires [67,66,68], nanobelts/ribbons [64,69], film structures [70], bone-like structures [71], nanosheets [72], nanopropeller arrays [73], nanorings/helixes [74], etc. In addition to the hydrothermal technique, various other techniques have been employed to prepare ZnO nanostructures like metal organic vapour phase epitaxy, laser ablation and thermal evaporation.…”

Electrode Spacing Effect on Ultraviolet Photoconductivity of Metal-Semiconductor-Metal Detectors with ZnO Nanorod Arrays Grown by Hydrothermal Method

“…An additional weak green emission band at 538 nm (2.30 eV) corresponding to the interstitial oxygen level is also observed. (24)(25)(26) The UV PDs having Au/ZnO/Au metal-semiconductor-metal structures with Au interdigitated electrodes simply patterned on the top of ZnO NR arrays were then evaluated. The I-V characteristics of these PDs measured under UV illumination at 380 nm and in the dark are shown This ohmic behavior can be explained by an increase in carrier concentration at the interface due to a high donor concentration contributed by oxygen vacancies in ZnO NRs, which leads to a low contact resistivity by increasing the electron tunneling probability through a narrow interface barrier.…”