Optical and electrical properties of hydrothermally grown Al-doped ZnO nanorods on graphene/Ni/Si substrate

We present a simple way to prepare low-resistance ZnO nanorods by hydrothermal self-assembled growth at 95 °C and in situ doped with Al. The NRs were grown on graphene/Ni/Si and annealed at 400 °C. Few layer graphene was used to assist aligned growth of the NRs and acted as an electrode during electric measurement. The measurement showed resistance of the Al-doped ZnO NRs 100 times lower than that of undoped ZnO NRs. Photoluminescence measurement showed enhanced deep level emission for the Al-doped NRs and low temperature photoluminescence study showed coexistence of acceptor bound-exciton (3.353 eV) and donor bound-exciton (3.362 eV).

► Low-resistivity Al-doped ZnO nanorods prepared by hydrothermal self-assembling.
► Utilization of few layer graphene in NR growth.
► Enhanced deep level photoluminescence and existence of acceptor bound- and donor bound-excitonsin Al–ZnO NRs.