In this paper, we adapted the Stranski-Krastanow (SK) mode to the heteroepitaxial growth of NWs and suggested three general growth modes (SK, island SK, and coherent SK) covering all phenomena observed from nanostructures epitaxially grown on single crystal substrates. A strain versus dislocation (SVD) model was also established to define these three modes. The SVD model analyzes the competitio...

Title of Dissertation: DEVELOPMENT OF SELF-ASSEMBLED ZnO NANOSTRUCTURES IN DIBLOCK COPOLYMERS ON LARGE AREA Si WAFERS AND GAS SENSOR APPLICATIONS Hasina Afroz Ali, Doctor of Philosophy, 2008 Dissertation Directed By: Agis A. Iliadis Department of Electrical and Computer Engineering ZnO nanoparticles with improved optical properties and increased surface areas have the potential for advanced opt...

ZnO thin films of porous structure with strong c-axis orientation were deposited on n-type silicon substrate by pulsed laser ablation of ZnO target in low O2 pressure (around 0.03 mbar) and at 600C substrate temperature. We attribute the formation of nanopores and the crater-like formation to the high kinetic energy of the ablated particles. Photoluminescence spectra show the near band edge emi...

We review the solvothermal synthesis, using a mixture of ethylene glycol (EG) and water as the solvent, of zinc oxide (ZnO) particles having spherical and flower-like shapes and hierarchical nanostructures. The preparation conditions of the ZnO particles and the microscopic characterization of the morphology are summarized. We found the following three effects of the ratio of EG to water on the...

Bottom-up synthesis of zinc oxide (ZnO) nanowires requires a highly engineered substrate to achieve alignment and orientation control. Here, we report textured ZnO film as an inexpensive substrate to fulfill the requirement. The textured film is coated conformally on various surface topographies and allows the epitaxial growth of ZnO nanowires with vertical, tilted, or lateral orientations. The...

One-dimensional (1D) semiconducting nanostructures, such as nanowires (NWs) and nanobelts (NBs), are fundamental building blocks for constructing nanoscale electronic devices because of their small size and the enhanced charge carrier mobility owing to 1D confinement. Considerable efforts have been devoted to energy-band engineering by doping for controlling their electrical properties and asse...

Aligned ZnO arrays with branched rods, hexagonal rods, quasi-round rods, hexagonal pyramids and porous nanostructures are constructed on zinc foil in the ionic liquid tetrabutylammonium hydroxide aqueous solution.

A ZnO branched-nanowire (BNW) photoanode was doped with N for use in a photoelectrochemical cell (PEC) to generate H2 from water splitting. First, ZnO BNWs were synthesized by chemical bath deposition method. Two experimental methods were used for N-doping: the time-controlled direct-current glow discharge plasma (DCGDP) and the DC magnetron plasma (DCMP) methods, to optimize N-doping of the NW...

Over the past few decades zinc oxide (ZnO)-based thin films and nanostructures have shown unprecedented performance in a wide range of applications. In particular, owing to high isoelectric point, biocompatibility and other multifunctional characteristics, ZnO has extensively been studied as a transduction material for biosensor development. The fascinating properties of ZnO help retain biologi...

We demonstrate the morphological control method of ZnO nanostructures by atomic layer deposition (ALD) on an Al2O3/ZnO seed layer surface and the application of a hierarchical ZnO nanostructure for a photodetector. Two layers of ZnO and Al2O3 prepared using ALD with different pH values in solution coexisted on the alloy film surface, leading to deactivation of the surface hydroxyl groups. This ...