Synthesis Of Zn_1-xMg_xO Nanorods Via Low Temperature Aqueous Method And Study Of Their Properties

Zinc oxide (ZnO) is one of the most potential wide energy gap materials due to its wide energy gap (3.37eV) and relatively large exciton binding energy (60meV) under room temperature. Therefore, ZnO has been regarded as one of the most potential materials for manufacturing the ultraviolet (UV) optoelectronic devices such as UV detectors and UV lasers. One dimensional ZnO nanomaterials have so many advantages such as the large specific surface area and good monocrystal quality. Consequently, ZnO nanomaterials have become more and more popupar in this field. Meanwhile, the research about the doping of the metal elements for ZnO has been proved that it can adjust the energy gap effectively which can lead to a more wider application of it. So the study of the doping of ZnO nanomaterials has caused great interest. Recently, there are constant reports about the progress we get in the doping of ZnO nanomaterials field, however the methods we adopted for instance pulsed laser deposition (PLD), metal-organic chemical vapor deposition (MOCVD) and electrochemical deposition are all cost way too much and also a littlt too complicate to operate. Hence, finding a way which is much cheaper and can be carried out in an easier way to dope a certain element into ZnO under a low temperature is becoming more and more urgent.In this paper, we synthetized Mg doped ZnO nanorods (ZnO:Mg) on silicon (si) substrate. First we get a medium ZnO seed layer through magnetron sputtering method by controlling the parameters. Then ZnO:Mg nanorods can be grown on the seed layer using low temperature aqueous method with different concentration of the Mg.The samples were measured by scanning electron microscope (SEM) which showed the morphology characteristic. We can clearly saw that the size of the nanorods became smaller with the increasing concentration of Mg which can be explained that the doping of Mg has been the obstacle in the growing process of the nanorods. The photoluminescence spectra demonstrated the optical properties of the samples which showed that all the three samples only owned a near band emission (NBE) and didn’t have the deep level related peak confirming the good crystal quality.Meanwhile, the comparison diagram of the three samples showed us that with the increasing of Mg’s doping concentration the NBE peak appeared a very obvious blue shift which confirmed that the doping of Mg has adjusted the energy gap of the nanorods effectively. Moreover the increase of the full width at half maximum (FWHM) also declared the bad effect on the crystal quality because of Mg’s doping. The samples were also measured using X-ray diffraction method to study its structure. The result showed that the peak angle of the doped nanorods were a little larger than the undoped ones. Meanwhile, the preferred orientation of the doped nanorods deteriorated. The experimental outcome and the analysis results both confirmed that Mg has definitely been doped into the nanorods and existed as Mgzn formation. Howerver, we can also see that the doping of Mg had a bad effection on the crystal quality.