| ZnO is a wide band semiconductor and the band gap is 3.37 eV at room temperature. The high exciton energy (60 meV) ensures high-efficient exciton emissions. It is worth noting that the radii of Mg2+ is similar to that of Zn2+. Meanwhile, the band gap of MgO is 7.9 eV at room temperature. Thereby it is possible to tune the value of band gap by forming the alloy of Zn1-xMgxO. This unique property makes Zn1-xMgxO promising for optical devices.We synthesized Zn1-xMgxO nanofibers with various values of"x"by electrospinning. polyvinyl alcohol (PVA Mn=80000)and inorganic salts(zinc acetate,magnesium acetate)was used as precusors. Zn1-xMgxO alloys were obtained by annealing the Zn1-xMgxO nanofibers.When using the polymer, we found that the density of PVA, usage of ethanol, the amount of inorganic salts as well as instrumental parameters such as receiving distance, voltage and the raising rate of annealing temperature are all important factors which influence the properties of nanofibers. We analyzed the samples through the measurement of scanning electron microscopy, photoluminescence, Raman scattering, X-ray diffraction, and ultraviolet absorption. For the Zn1-xMgxO alloys, the intensity of optical emissions increased with increasing the value of"x". When x>0.05(x=0.05,0.10,0.15,0.20), phase separation occurred.Based on the results, we obtained the emission rule for Zn1-xMgxO with various values of"x", and analyzed the mechanism of the change of structural and optical properties.
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