Structural order in single Co-implanted ZnO nanowires

In this work, we report on the short and long range order of single room temperature-implanted and high temperature-implanted Co:ZnO nanowires using hard X-ray nanoprobe-based techniques. X-ray fluorescence maps reveal a homogeneous distribution of the Co ions implanted along the nanowires. X-ray absorption near edge structure data indicate a substitutional incorporation of Co2+ into the wurtzite ZnO host lattice. The room temperature-implanted nanowires present a higher structural disorder around Co atoms compared to the high temperature-implanted ones. X-ray diffraction results show a crystal lattice expansion induced by the ion implantation process in the room temperature-implanted nanowires. Micro-photoluminescence data corroborate these findings and exhibit an excellent optical activation of the incorporated Co ions in the high temperature-implanted nanowires.