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  • A Comparative Study of Structural, Optical and Electrical Properties of Fe-ZnO Nanoparticles Synthesized by Precipitation and Microwave Method for Photovoltaic Applications
Title: A Comparative Study of Structural, Optical and Electrical Properties of Fe-ZnO Nanoparticles Synthesized by Precipitation and Microwave Method for Photovoltaic Applications
Iron doped ZnO (Fe-ZnO) nanoparticles were synthesized using two techniques that are economical as well as scalable to yield tunable properties of nanoparticles for facilitating down conversion in an absorbing layer of a solar cell. To evaluate the suitability of Fe-ZnO nanoparticles prepared by two deposition methods, we present a comparison of optical, electrical, and structural properties of Fe-ZnO using several experimental techniques. Structural properties were analyzed using transmission electron microscopy and x-ray diffraction spectroscopy (XRD) with Rietveld analysis for extracting information on compositional variations with Fe doping. The chemical composition of nanoparticles was analyzed through X-ray photoelectron spectroscopy (XPS). The optical properties of nanoparticles were studied using photoluminescence and UV-Vis absorption spectroscopy. In addition, fluorescence lifetime measurement was also performed to study the changes in an exponential decay of lifetimes. The electrical transport properties of Fe-ZnO were analyzed by impedance spectroscopy. Our studies indicate that ethanol as a solvent in a microwave method would produce smaller nanoparticles up to the size of 11 nm. In contrast, the precipitation method produces secondary phases of Fe2O3 beyond 5% doping. In addition, our studies show that the optical and electrical properties of resulting Fe-ZnO nanoparticles depend on the particle sizes and the synthesis techniques used. These new results provide insight into the role of solvents in fabricating Fe-ZnO nanoparticles by precipitation and microwave methods for photovoltaic and other applications.  more » « less
Award ID(s):
1828477
PAR ID:
10314448
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Energy and Power Technology
Volume:
03
Issue:
03
ISSN:
2690-1692
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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