Photoluminescence and Raman Spectroscopy of Polycrystalline ZnO Nanofibers Deposited by Electrospinning

• Published in: Journal of electronic materials 2011-09, Vol.40 (9), p.2015-2019
• Main Authors: Sen, Banani, Stroscio, Michael, Dutta, Mitra
• Format: Article
• Language: English
• Subjects: Carrier recombination; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Electrical engineering; Electronics and Microelectronics; Electrospinning; Exact sciences and technology; Instrumentation; Materials Science; Methods of nanofabrication; Nanocrystals and nanoparticles; Nanofibers; Nanomaterials; Nanoscale materials and structures: fabrication and characterization; Nanowires; Optical and Electronic Materials; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Photoluminescence; Physics; Quantum wires; Raman spectroscopy; Solid State Physics; Spectrum analysis; Zinc oxide; Zinc oxides
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-011-1688-8

The technique of electrospinning offers the advantage of growing nanowires in bulk quantities in comparison with traditional methods. We report optical studies of polycrystalline zinc oxide (ZnO) nanofibers (∼100 nm thick and 5  μ m long) deposited by electrospinning. Photoluminescence from the nanofibers shows a near-ultraviolet (near-UV) peak corresponding to near-band-edge emission and a strong broad peak in the visible region from oxygen antisite and interstitial defects. Temperature-dependent photoluminescence spectroscopy reveals that different carrier recombination mechanisms are dominant at low temperature. Our Raman spectroscopy results demonstrate that characterization of the quasimodes of longitudinal optical (LO) and transverse optical (TO) phonons present in an ensemble of polycrystalline nanofibers tilted at various angles in addition to the dominant E 2 (high) mode provides a promising technique for assessing the quality of such randomly oriented nanowires.