Introduction
Experimental methods
Results and discussion
Fig.1 (a) Top-view of the patterned and aligned ZnO nanorod arrays on the H2-decomposed GaN epilayer grown by hydrothermal reaction; (b, c) top-view and 30° tilt view nanorods assembled a hexagonal pattern; (d, e) other nanorods distributed perpendicular to the GaN epilayer surface without regular distribution |
Fig.2 (a) XRD pattern of ZnO nanorod arrays on the H2-decomposed GaN epilayer; (b) HRTEM image of a single ZnO nanorod confirming growth along the [0001] direction, inset is a low-resolution bright-field TEM image of the corresponding single ZnO nanorod where the area of analysis is indicated by the black circle |
Fig.3 Patterned ZnO nanorod arrays on H2-decomposed GaN epilayer growing at different solution concentrations, growth times and reaction temperatures. (A1, A2) 0.002 and 0.01 mol/L, 105°C for 2 h; (B1, B2) 4 and 7 h, 0.05 mol/L for 105°C; (C1, C2) 125 and 160°C, 0.05 mol/L for 4 h; (D1, D2) SEM images of ZnO nanorod growing on GaN epilayer without decomposition |
Tab.1 Experimental conditions of ZnO nanorod growing at different solution concentration, growth time and reaction temperature |
samples | concentration/(mol∙L-1) | growth time/h | temperature/°C |
---|---|---|---|
A1 A2 B1 B2 C1 C2 | 0.002 0.01 0.05 0.05 0.05 0.05 | 2 2 4 7 4 4 | 105 105 105 105 125 160 |