Electrospun ZnO precursor nanofibers of average diameters 122 ± 64. nm, 117 ± 44. nm and 110 ± 39. nm were fabricated by controlling the Al concentration of a polymeric solution. The resulting nanofibers were characterized by the XRD, SEM, EDS, TEM, XPS and PL. The electrospun Al-doped ZnO nanofiber films were polycrystalline and composed of densely packed grains, with crystallite size ranging from 28.7. nm, 25.7. nm, 25.4. nm to 20.4. nm corresponding to the atomic concentration of aluminum from 0, 1.6, 2.5 to 5.8. at.%. The incorporation of aluminum resulted in a decrease trend in the grain size and lattice parameter of the ZnO nanofiber films. The room temperature PL spectra of all samples show three different emissions, including UV (ultraviolet) emission with an obvious blue shift, Vis (visible) emission and NIR (near infrared) emission, the intensity of which decreases monotonically as the doping concentration is increased except for the highest doping level. The impurity content correlates with changes in the PL spectra, and the appropriate Al doping can improve the optical properties of ZnO nanofibers. The small size effect and Al-doping or the impurity incorporation should be responsible for the blue shift observation in Al-doped ZnO nanofiber films.
Bibliographical noteFunding Information:
The authors acknowledge the financial support of the Scientific Research Program Funded by Shaanxi Provincial Education Department (Program No. 2010JK655). This work was partially supported by the Project of Science and Technology for Returned Overseas Research Fellow through Shaanxi Administration of Foreign Expert Affairs, by SRF for ROCS, SEM and by the PUNAI Education Scholarship through Puyang Refractory Group Co., Ltd. (PRCO). The authors are grateful to Jing Shi of Xi’an Jiaotong University for the contribution to TEM measurement.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry