Temperature-dependent photoluminescence analysis of ZnO nanowire array annealed in air

ZnO nanowire arrays (NWAs) were prepared on transparent conducting fluorine doped tin oxide (FTO) substrates through a facile hydrothermal method, followed by a 500 degrees C annealing to improve their crystalline qualities and photoelectrochemical (PEC) activities. It was found that the annealing didn't change the morphology, but resulted in a significant reduction of the donor concentration. Temperature-dependent photoluminescence (PL) was carried out for a comprehensive analysis of the effect from annealing. Noteworthy, four dominant peaks were identified from the 101< spectrum of a 500 degrees C annealed sample, and they were assigned to FX, (DX)-X-0, (e, D-0) and (e, D-0)-ILO, respectively. Of them, the FX emission was only existed below 130 K, while the room-temperature (RT) PL spectrum was dominated by the (DX)-X-0 emission. (C) 2018 Elsevier Ltd. All rights reserved.