We present a simple way to prepare low-resistance ZnO nanorods by hydrothermal self-assembled growth at 95 degrees C and in situ doped with Al. The NRs were grown on graphene/Ni/Si and annealed at 400 degrees 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). (C) 2013 Elsevier Ltd. All rights reserved.