Dependence of optical properties of Mg-doped ZnO nanorods on Al dopant

We have synthesized Mg-doped ZnO and Al-Mg co-doped ZnO nanorods with various Al/Zn ratios of 1%, 2%, 3% by hydrothermal at 95 °C for 6 h. Morphologically, the Mg-doped and Al-Mg co-doped ZnO nanorods have a clear hexagonal shape. According to the inorganic crystal structure database (ICSD) number #98-002-9272, all samples possess polycrystalline wurtzite structure and preferred orientation in (002) plane. The crystallite size and micro-strain changed with Al incorporation into Mg-doped ZnO nanorods. Optical bandgap energy of the Al-Mg co-doped ZnO nanorods indicates that the increasing Al content decreases bandgap energy linearly. The influence of Al dopants on optical properties of Mg-doped ZnO nanorods causes blue shifts of UV emission which is due to the Burstein-Moss (BM) effect.